ac383024dd8c233d53163b1da342e8b287b724b1
[l2tpns.git] / l2tpns.c
1 // L2TP Network Server
2 // Adrian Kennard 2002
3 // Copyright (c) 2003, 2004, 2005 Optus Internet Engineering
4 // Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced
5 // vim: sw=8 ts=8
6
7 char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.158 2006-04-05 01:50:33 bodea Exp $";
8
9 #include <arpa/inet.h>
10 #include <assert.h>
11 #include <errno.h>
12 #include <fcntl.h>
13 #include <linux/if_tun.h>
14 #define SYSLOG_NAMES
15 #include <syslog.h>
16 #include <malloc.h>
17 #include <math.h>
18 #include <net/route.h>
19 #include <sys/mman.h>
20 #include <netdb.h>
21 #include <netinet/in.h>
22 #include <netinet/ip6.h>
23 #include <stdarg.h>
24 #include <stdlib.h>
25 #include <stdio.h>
26 #include <string.h>
27 #include <ctype.h>
28 #include <sys/ioctl.h>
29 #include <sys/socket.h>
30 #include <sys/stat.h>
31 #include <sys/time.h>
32 #include <sys/resource.h>
33 #include <sys/wait.h>
34 #include <linux/if.h>
35 #include <stddef.h>
36 #include <time.h>
37 #include <dlfcn.h>
38 #include <unistd.h>
39 #include <sched.h>
40 #include <sys/sysinfo.h>
41 #include <libcli.h>
42
43 #include "md5.h"
44 #include "l2tpns.h"
45 #include "cluster.h"
46 #include "plugin.h"
47 #include "ll.h"
48 #include "constants.h"
49 #include "control.h"
50 #include "util.h"
51 #include "tbf.h"
52
53 #ifdef BGP
54 #include "bgp.h"
55 #endif
56
57 // Globals
58 configt *config = NULL; // all configuration
59 int tunfd = -1; // tun interface file handle. (network device)
60 int udpfd = -1; // UDP file handle
61 int controlfd = -1; // Control signal handle
62 int clifd = -1; // Socket listening for CLI connections.
63 int daefd = -1; // Socket listening for DAE connections.
64 int snoopfd = -1; // UDP file handle for sending out intercept data
65 int *radfds = NULL; // RADIUS requests file handles
66 int ifrfd = -1; // File descriptor for routing, etc
67 int ifr6fd = -1; // File descriptor for IPv6 routing, etc
68 int rand_fd = -1; // Random data source
69 int cluster_sockfd = -1; // Intra-cluster communications socket.
70 int epollfd = -1; // event polling
71 time_t basetime = 0; // base clock
72 char hostname[1000] = ""; // us.
73 static int tunidx; // ifr_ifindex of tun device
74 static int syslog_log = 0; // are we logging to syslog
75 static FILE *log_stream = 0; // file handle for direct logging (i.e. direct into file, not via syslog).
76 uint32_t last_id = 0; // Unique ID for radius accounting
77
78 // calculated from config->l2tp_mtu
79 uint16_t MRU = 0; // PPP MRU
80 uint16_t MSS = 0; // TCP MSS
81
82 struct cli_session_actions *cli_session_actions = NULL; // Pending session changes requested by CLI
83 struct cli_tunnel_actions *cli_tunnel_actions = NULL; // Pending tunnel changes required by CLI
84
85 static void *ip_hash[256]; // Mapping from IP address to session structures.
86 struct ipv6radix {
87 int sess;
88 struct ipv6radix *branch;
89 } ipv6_hash[256]; // Mapping from IPv6 address to session structures.
90
91 // Traffic counters.
92 static uint32_t udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
93 static uint32_t eth_rx = 0, eth_rx_pkt = 0;
94 uint32_t eth_tx = 0;
95
96 static uint32_t ip_pool_size = 1; // Size of the pool of addresses used for dynamic address allocation.
97 time_t time_now = 0; // Current time in seconds since epoch.
98 static char time_now_string[64] = {0}; // Current time as a string.
99 static int time_changed = 0; // time_now changed
100 char main_quit = 0; // True if we're in the process of exiting.
101 static char main_reload = 0; // Re-load pending
102 linked_list *loaded_plugins;
103 linked_list *plugins[MAX_PLUGIN_TYPES];
104
105 #define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
106 #define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(configt, MEMBER), membersize(configt, MEMBER), TYPE }
107
108 config_descriptt config_values[] = {
109 CONFIG("debug", debug, INT),
110 CONFIG("log_file", log_filename, STRING),
111 CONFIG("pid_file", pid_file, STRING),
112 CONFIG("random_device", random_device, STRING),
113 CONFIG("l2tp_secret", l2tp_secret, STRING),
114 CONFIG("l2tp_mtu", l2tp_mtu, INT),
115 CONFIG("ppp_restart_time", ppp_restart_time, INT),
116 CONFIG("ppp_max_configure", ppp_max_configure, INT),
117 CONFIG("ppp_max_failure", ppp_max_failure, INT),
118 CONFIG("primary_dns", default_dns1, IPv4),
119 CONFIG("secondary_dns", default_dns2, IPv4),
120 CONFIG("primary_radius", radiusserver[0], IPv4),
121 CONFIG("secondary_radius", radiusserver[1], IPv4),
122 CONFIG("primary_radius_port", radiusport[0], SHORT),
123 CONFIG("secondary_radius_port", radiusport[1], SHORT),
124 CONFIG("radius_accounting", radius_accounting, BOOL),
125 CONFIG("radius_interim", radius_interim, INT),
126 CONFIG("radius_secret", radiussecret, STRING),
127 CONFIG("radius_authtypes", radius_authtypes_s, STRING),
128 CONFIG("radius_dae_port", radius_dae_port, SHORT),
129 CONFIG("allow_duplicate_users", allow_duplicate_users, BOOL),
130 CONFIG("bind_address", bind_address, IPv4),
131 CONFIG("peer_address", peer_address, IPv4),
132 CONFIG("send_garp", send_garp, BOOL),
133 CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
134 CONFIG("throttle_buckets", num_tbfs, INT),
135 CONFIG("accounting_dir", accounting_dir, STRING),
136 CONFIG("setuid", target_uid, INT),
137 CONFIG("dump_speed", dump_speed, BOOL),
138 CONFIG("multi_read_count", multi_read_count, INT),
139 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
140 CONFIG("lock_pages", lock_pages, BOOL),
141 CONFIG("icmp_rate", icmp_rate, INT),
142 CONFIG("packet_limit", max_packets, INT),
143 CONFIG("cluster_address", cluster_address, IPv4),
144 CONFIG("cluster_interface", cluster_interface, STRING),
145 CONFIG("cluster_mcast_ttl", cluster_mcast_ttl, INT),
146 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
147 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
148 CONFIG("cluster_master_min_adv", cluster_master_min_adv, INT),
149 CONFIG("ipv6_prefix", ipv6_prefix, IPv6),
150 { NULL, 0, 0, 0 },
151 };
152
153 static char *plugin_functions[] = {
154 NULL,
155 "plugin_pre_auth",
156 "plugin_post_auth",
157 "plugin_packet_rx",
158 "plugin_packet_tx",
159 "plugin_timer",
160 "plugin_new_session",
161 "plugin_kill_session",
162 "plugin_control",
163 "plugin_radius_response",
164 "plugin_radius_reset",
165 "plugin_radius_account",
166 "plugin_become_master",
167 "plugin_new_session_master",
168 };
169
170 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
171
172 // Counters for shutdown sessions
173 static sessiont shut_acct[8192];
174 static sessionidt shut_acct_n = 0;
175
176 tunnelt *tunnel = NULL; // Array of tunnel structures.
177 sessiont *session = NULL; // Array of session structures.
178 sessionlocalt *sess_local = NULL; // Array of local per-session counters.
179 radiust *radius = NULL; // Array of radius structures.
180 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
181 ip_filtert *ip_filters = NULL; // Array of named filters.
182 static controlt *controlfree = 0;
183 struct Tstats *_statistics = NULL;
184 #ifdef RINGBUFFER
185 struct Tringbuffer *ringbuffer = NULL;
186 #endif
187
188 static void cache_ipmap(in_addr_t ip, int s);
189 static void uncache_ipmap(in_addr_t ip);
190 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s);
191 static void free_ip_address(sessionidt s);
192 static void dump_acct_info(int all);
193 static void sighup_handler(int sig);
194 static void shutdown_handler(int sig);
195 static void sigchild_handler(int sig);
196 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response);
197 static void update_config(void);
198 static void read_config_file(void);
199 static void initplugins(void);
200 static int add_plugin(char *plugin_name);
201 static int remove_plugin(char *plugin_name);
202 static void plugins_done(void);
203 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struct in_addr *local);
204 static tunnelidt new_tunnel(void);
205 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len);
206
207 // on slaves, alow BGP to withdraw cleanly before exiting
208 #define QUIT_DELAY 5
209
210 // quit actions (master)
211 #define QUIT_FAILOVER 1 // SIGTERM: exit when all control messages have been acked (for cluster failover)
212 #define QUIT_SHUTDOWN 2 // SIGQUIT: shutdown sessions/tunnels, reject new connections
213
214 // return internal time (10ths since process startup), set f if given
215 // as a side-effect sets time_now, and time_changed
216 static clockt now(double *f)
217 {
218 struct timeval t;
219 gettimeofday(&t, 0);
220 if (f) *f = t.tv_sec + t.tv_usec / 1000000.0;
221 if (t.tv_sec != time_now)
222 {
223 time_now = t.tv_sec;
224 time_changed++;
225 }
226 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
227 }
228
229 // work out a retry time based on try number
230 // This is a straight bounded exponential backoff.
231 // Maximum re-try time is 32 seconds. (2^5).
232 clockt backoff(uint8_t try)
233 {
234 if (try > 5) try = 5; // max backoff
235 return now(NULL) + 10 * (1 << try);
236 }
237
238
239 //
240 // Log a debug message. Typically called via the LOG macro
241 //
242 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
243 {
244 static char message[65536] = {0};
245 va_list ap;
246
247 #ifdef RINGBUFFER
248 if (ringbuffer)
249 {
250 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
251 ringbuffer->tail = 0;
252 if (ringbuffer->tail == ringbuffer->head)
253 if (++ringbuffer->head >= RINGBUFFER_SIZE)
254 ringbuffer->head = 0;
255
256 ringbuffer->buffer[ringbuffer->tail].level = level;
257 ringbuffer->buffer[ringbuffer->tail].session = s;
258 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
259 va_start(ap, format);
260 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
261 va_end(ap);
262 }
263 #endif
264
265 if (config->debug < level) return;
266
267 va_start(ap, format);
268 vsnprintf(message, sizeof(message), format, ap);
269
270 if (log_stream)
271 fprintf(log_stream, "%s %02d/%02d %s", time_now_string, t, s, message);
272 else if (syslog_log)
273 syslog(level + 2, "%02d/%02d %s", t, s, message); // We don't need LOG_EMERG or LOG_ALERT
274
275 va_end(ap);
276 }
277
278 void _log_hex(int level, const char *title, const uint8_t *data, int maxsize)
279 {
280 int i, j;
281 const uint8_t *d = data;
282
283 if (config->debug < level) return;
284
285 // No support for _log_hex to syslog
286 if (log_stream)
287 {
288 _log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
289 setvbuf(log_stream, NULL, _IOFBF, 16384);
290
291 for (i = 0; i < maxsize; )
292 {
293 fprintf(log_stream, "%4X: ", i);
294 for (j = i; j < maxsize && j < (i + 16); j++)
295 {
296 fprintf(log_stream, "%02X ", d[j]);
297 if (j == i + 7)
298 fputs(": ", log_stream);
299 }
300
301 for (; j < i + 16; j++)
302 {
303 fputs(" ", log_stream);
304 if (j == i + 7)
305 fputs(": ", log_stream);
306 }
307
308 fputs(" ", log_stream);
309 for (j = i; j < maxsize && j < (i + 16); j++)
310 {
311 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
312 fputc(d[j], log_stream);
313 else
314 fputc('.', log_stream);
315
316 if (j == i + 7)
317 fputs(" ", log_stream);
318 }
319
320 i = j;
321 fputs("\n", log_stream);
322 }
323
324 fflush(log_stream);
325 setbuf(log_stream, NULL);
326 }
327 }
328
329 // update a counter, accumulating 2^32 wraps
330 void increment_counter(uint32_t *counter, uint32_t *wrap, uint32_t delta)
331 {
332 uint32_t new = *counter + delta;
333 if (new < *counter)
334 (*wrap)++;
335
336 *counter = new;
337 }
338
339 // initialise the random generator
340 static void initrandom(char *source)
341 {
342 static char path[sizeof(config->random_device)] = "*undefined*";
343
344 // reinitialise only if we are forced to do so or if the config has changed
345 if (source && !strncmp(path, source, sizeof(path)))
346 return;
347
348 // close previous source, if any
349 if (rand_fd >= 0)
350 close(rand_fd);
351
352 rand_fd = -1;
353
354 if (source)
355 {
356 // register changes
357 snprintf(path, sizeof(path), "%s", source);
358
359 if (*path == '/')
360 {
361 rand_fd = open(path, O_RDONLY|O_NONBLOCK);
362 if (rand_fd < 0)
363 LOG(0, 0, 0, "Error opening the random device %s: %s\n",
364 path, strerror(errno));
365 }
366 }
367 }
368
369 // fill buffer with random data
370 void random_data(uint8_t *buf, int len)
371 {
372 int n = 0;
373
374 CSTAT(random_data);
375 if (rand_fd >= 0)
376 {
377 n = read(rand_fd, buf, len);
378 if (n >= len) return;
379 if (n < 0)
380 {
381 if (errno != EAGAIN)
382 {
383 LOG(0, 0, 0, "Error reading from random source: %s\n",
384 strerror(errno));
385
386 // fall back to rand()
387 initrandom(NULL);
388 }
389
390 n = 0;
391 }
392 }
393
394 // append missing data
395 while (n < len)
396 // not using the low order bits from the prng stream
397 buf[n++] = (rand() >> 4) & 0xff;
398 }
399
400 // Add a route
401 //
402 // This adds it to the routing table, advertises it
403 // via BGP if enabled, and stuffs it into the
404 // 'sessionbyip' cache.
405 //
406 // 'ip' and 'mask' must be in _host_ order.
407 //
408 static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, int add)
409 {
410 struct rtentry r;
411 int i;
412
413 if (!mask) mask = 0xffffffff;
414
415 ip &= mask; // Force the ip to be the first one in the route.
416
417 memset(&r, 0, sizeof(r));
418 r.rt_dev = config->tundevice;
419 r.rt_dst.sa_family = AF_INET;
420 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
421 r.rt_gateway.sa_family = AF_INET;
422 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
423 r.rt_genmask.sa_family = AF_INET;
424 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
425 r.rt_flags = (RTF_UP | RTF_STATIC);
426 if (gw)
427 r.rt_flags |= RTF_GATEWAY;
428 else if (mask == 0xffffffff)
429 r.rt_flags |= RTF_HOST;
430
431 LOG(1, s, 0, "Route %s %s/%s%s%s\n", add ? "add" : "del",
432 fmtaddr(htonl(ip), 0), fmtaddr(htonl(mask), 1),
433 gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
434
435 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
436 LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
437
438 #ifdef BGP
439 if (add)
440 bgp_add_route(htonl(ip), htonl(mask));
441 else
442 bgp_del_route(htonl(ip), htonl(mask));
443 #endif /* BGP */
444
445 // Add/Remove the IPs to the 'sessionbyip' cache.
446 // Note that we add the zero address in the case of
447 // a network route. Roll on CIDR.
448
449 // Note that 's == 0' implies this is the address pool.
450 // We still cache it here, because it will pre-fill
451 // the malloc'ed tree.
452
453 if (s)
454 {
455 if (!add) // Are we deleting a route?
456 s = 0; // Caching the session as '0' is the same as uncaching.
457
458 for (i = ip; (i&mask) == (ip&mask) ; ++i)
459 cache_ipmap(i, s);
460 }
461 }
462
463 void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
464 {
465 struct in6_rtmsg rt;
466 char ipv6addr[INET6_ADDRSTRLEN];
467
468 if (ifr6fd < 0)
469 {
470 LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n");
471 return;
472 }
473
474 memset(&rt, 0, sizeof(rt));
475
476 memcpy(&rt.rtmsg_dst, &ip, sizeof(struct in6_addr));
477 rt.rtmsg_dst_len = prefixlen;
478 rt.rtmsg_metric = 1;
479 rt.rtmsg_flags = RTF_UP;
480 rt.rtmsg_ifindex = tunidx;
481
482 LOG(1, 0, 0, "Route %s %s/%d\n",
483 add ? "add" : "del",
484 inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN),
485 prefixlen);
486
487 if (ioctl(ifr6fd, add ? SIOCADDRT : SIOCDELRT, (void *) &rt) < 0)
488 LOG(0, 0, 0, "route6set() error in ioctl: %s\n",
489 strerror(errno));
490
491 // FIXME: need to add BGP routing (RFC2858)
492
493 if (s)
494 {
495 if (!add) // Are we deleting a route?
496 s = 0; // Caching the session as '0' is the same as uncaching.
497
498 cache_ipv6map(ip, prefixlen, s);
499 }
500
501 return;
502 }
503
504 // defined in linux/ipv6.h, but tricky to include from user-space
505 // TODO: move routing to use netlink rather than ioctl
506 struct in6_ifreq {
507 struct in6_addr ifr6_addr;
508 __u32 ifr6_prefixlen;
509 unsigned int ifr6_ifindex;
510 };
511
512 //
513 // Set up TUN interface
514 static void inittun(void)
515 {
516 struct ifreq ifr;
517 struct in6_ifreq ifr6;
518 struct sockaddr_in sin = {0};
519 memset(&ifr, 0, sizeof(ifr));
520 ifr.ifr_flags = IFF_TUN;
521
522 tunfd = open(TUNDEVICE, O_RDWR);
523 if (tunfd < 0)
524 { // fatal
525 LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
526 exit(1);
527 }
528 {
529 int flags = fcntl(tunfd, F_GETFL, 0);
530 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
531 }
532 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
533 {
534 LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
535 exit(1);
536 }
537 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
538 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
539 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
540
541 sin.sin_family = AF_INET;
542 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
543 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
544
545 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
546 {
547 LOG(0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
548 exit(1);
549 }
550 /* Bump up the qlen to deal with bursts from the network */
551 ifr.ifr_qlen = 1000;
552 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
553 {
554 LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
555 exit(1);
556 }
557 /* set MTU to modem MRU */
558 ifr.ifr_mtu = MRU;
559 if (ioctl(ifrfd, SIOCSIFMTU, (void *) &ifr) < 0)
560 {
561 LOG(0, 0, 0, "Error setting tun MTU: %s\n", strerror(errno));
562 exit(1);
563 }
564 ifr.ifr_flags = IFF_UP;
565 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
566 {
567 LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
568 exit(1);
569 }
570 if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
571 {
572 LOG(0, 0, 0, "Error getting tun ifindex: %s\n", strerror(errno));
573 exit(1);
574 }
575 tunidx = ifr.ifr_ifindex;
576
577 // Only setup IPv6 on the tun device if we have a configured prefix
578 if (config->ipv6_prefix.s6_addr[0]) {
579 ifr6fd = socket(PF_INET6, SOCK_DGRAM, 0);
580
581 // Link local address is FE80::1
582 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
583 ifr6.ifr6_addr.s6_addr[0] = 0xFE;
584 ifr6.ifr6_addr.s6_addr[1] = 0x80;
585 ifr6.ifr6_addr.s6_addr[15] = 1;
586 ifr6.ifr6_prefixlen = 64;
587 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
588 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
589 {
590 LOG(0, 0, 0, "Error setting tun IPv6 link local address:"
591 " %s\n", strerror(errno));
592 }
593
594 // Global address is prefix::1
595 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
596 ifr6.ifr6_addr = config->ipv6_prefix;
597 ifr6.ifr6_addr.s6_addr[15] = 1;
598 ifr6.ifr6_prefixlen = 64;
599 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
600 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
601 {
602 LOG(0, 0, 0, "Error setting tun IPv6 global address: %s\n",
603 strerror(errno));
604 }
605 }
606 }
607
608 // set up UDP ports
609 static void initudp(void)
610 {
611 int on = 1;
612 struct sockaddr_in addr;
613
614 // Tunnel
615 memset(&addr, 0, sizeof(addr));
616 addr.sin_family = AF_INET;
617 addr.sin_port = htons(L2TPPORT);
618 addr.sin_addr.s_addr = config->bind_address;
619 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
620 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
621 {
622 int flags = fcntl(udpfd, F_GETFL, 0);
623 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
624 }
625 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
626 {
627 LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
628 exit(1);
629 }
630
631 // Control
632 memset(&addr, 0, sizeof(addr));
633 addr.sin_family = AF_INET;
634 addr.sin_port = htons(NSCTL_PORT);
635 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
636 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
637 setsockopt(controlfd, SOL_IP, IP_PKTINFO, &on, sizeof(on)); // recvfromto
638 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
639 {
640 LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
641 exit(1);
642 }
643
644 // Dynamic Authorization Extensions to RADIUS
645 memset(&addr, 0, sizeof(addr));
646 addr.sin_family = AF_INET;
647 addr.sin_port = htons(config->radius_dae_port);
648 daefd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
649 setsockopt(daefd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
650 if (bind(daefd, (void *) &addr, sizeof(addr)) < 0)
651 {
652 LOG(0, 0, 0, "Error in DAE bind: %s\n", strerror(errno));
653 exit(1);
654 }
655
656 // Intercept
657 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
658 }
659
660 //
661 // Find session by IP, < 1 for not found
662 //
663 // Confusingly enough, this 'ip' must be
664 // in _network_ order. This being the common
665 // case when looking it up from IP packet headers.
666 //
667 // We actually use this cache for two things.
668 // #1. For used IP addresses, this maps to the
669 // session ID that it's used by.
670 // #2. For un-used IP addresses, this maps to the
671 // index into the pool table that contains that
672 // IP address.
673 //
674
675 static int lookup_ipmap(in_addr_t ip)
676 {
677 uint8_t *a = (uint8_t *) &ip;
678 uint8_t **d = (uint8_t **) ip_hash;
679
680 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
681 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
682 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
683
684 return (int) (intptr_t) d[(size_t) *a];
685 }
686
687 static int lookup_ipv6map(struct in6_addr ip)
688 {
689 struct ipv6radix *curnode;
690 int i;
691 int s;
692 char ipv6addr[INET6_ADDRSTRLEN];
693
694 curnode = &ipv6_hash[ip.s6_addr[0]];
695 i = 1;
696 s = curnode->sess;
697
698 while (s == 0 && i < 15 && curnode->branch != NULL)
699 {
700 curnode = &curnode->branch[ip.s6_addr[i]];
701 s = curnode->sess;
702 i++;
703 }
704
705 LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
706 inet_ntop(AF_INET6, &ip, ipv6addr,
707 INET6_ADDRSTRLEN),
708 s);
709
710 return s;
711 }
712
713 sessionidt sessionbyip(in_addr_t ip)
714 {
715 int s = lookup_ipmap(ip);
716 CSTAT(sessionbyip);
717
718 if (s > 0 && s < MAXSESSION && session[s].opened)
719 return (sessionidt) s;
720
721 return 0;
722 }
723
724 sessionidt sessionbyipv6(struct in6_addr ip)
725 {
726 int s;
727 CSTAT(sessionbyipv6);
728
729 if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
730 (ip.s6_addr[0] == 0xFE &&
731 ip.s6_addr[1] == 0x80 &&
732 ip.s6_addr16[1] == 0 &&
733 ip.s6_addr16[2] == 0 &&
734 ip.s6_addr16[3] == 0)) {
735 s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
736 } else {
737 s = lookup_ipv6map(ip);
738 }
739
740 if (s > 0 && s < MAXSESSION && session[s].opened)
741 return s;
742
743 return 0;
744 }
745
746 //
747 // Take an IP address in HOST byte order and
748 // add it to the sessionid by IP cache.
749 //
750 // (It's actually cached in network order)
751 //
752 static void cache_ipmap(in_addr_t ip, int s)
753 {
754 in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
755 uint8_t *a = (uint8_t *) &nip;
756 uint8_t **d = (uint8_t **) ip_hash;
757 int i;
758
759 for (i = 0; i < 3; i++)
760 {
761 if (!d[(size_t) a[i]])
762 {
763 if (!(d[(size_t) a[i]] = calloc(256, sizeof(void *))))
764 return;
765 }
766
767 d = (uint8_t **) d[(size_t) a[i]];
768 }
769
770 d[(size_t) a[3]] = (uint8_t *) (intptr_t) s;
771
772 if (s > 0)
773 LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
774
775 else if (s == 0)
776 LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
777 // else a map to an ip pool index.
778 }
779
780 static void uncache_ipmap(in_addr_t ip)
781 {
782 cache_ipmap(ip, 0); // Assign it to the NULL session.
783 }
784
785 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s)
786 {
787 int i;
788 int bytes;
789 struct ipv6radix *curnode;
790 char ipv6addr[INET6_ADDRSTRLEN];
791
792 curnode = &ipv6_hash[ip.s6_addr[0]];
793
794 bytes = prefixlen >> 3;
795 i = 1;
796 while (i < bytes) {
797 if (curnode->branch == NULL)
798 {
799 if (!(curnode->branch = calloc(256,
800 sizeof (struct ipv6radix))))
801 return;
802 }
803 curnode = &curnode->branch[ip.s6_addr[i]];
804 i++;
805 }
806
807 curnode->sess = s;
808
809 if (s > 0)
810 LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
811 inet_ntop(AF_INET6, &ip, ipv6addr,
812 INET6_ADDRSTRLEN),
813 prefixlen);
814 else if (s == 0)
815 LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
816 inet_ntop(AF_INET6, &ip, ipv6addr,
817 INET6_ADDRSTRLEN),
818 prefixlen);
819 }
820
821 //
822 // CLI list to dump current ipcache.
823 //
824 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
825 {
826 char **d = (char **) ip_hash, **e, **f, **g;
827 int i, j, k, l;
828 int count = 0;
829
830 if (CLI_HELP_REQUESTED)
831 return CLI_HELP_NO_ARGS;
832
833 cli_print(cli, "%7s %s", "Sess#", "IP Address");
834
835 for (i = 0; i < 256; ++i)
836 {
837 if (!d[i])
838 continue;
839 e = (char **) d[i];
840 for (j = 0; j < 256; ++j)
841 {
842 if (!e[j])
843 continue;
844 f = (char **) e[j];
845 for (k = 0; k < 256; ++k)
846 {
847 if (!f[k])
848 continue;
849 g = (char **)f[k];
850 for (l = 0; l < 256; ++l)
851 {
852 if (!g[l])
853 continue;
854 cli_print(cli, "%7d %d.%d.%d.%d", (int) (intptr_t) g[l], i, j, k, l);
855 ++count;
856 }
857 }
858 }
859 }
860 cli_print(cli, "%d entries in cache", count);
861 return CLI_OK;
862 }
863
864
865 // Find session by username, 0 for not found
866 // walled garden users aren't authenticated, so the username is
867 // reasonably useless. Ignore them to avoid incorrect actions
868 //
869 // This is VERY inefficent. Don't call it often. :)
870 //
871 sessionidt sessionbyuser(char *username)
872 {
873 int s;
874 CSTAT(sessionbyuser);
875
876 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
877 {
878 if (!session[s].opened)
879 continue;
880
881 if (session[s].walled_garden)
882 continue; // Skip walled garden users.
883
884 if (!strncmp(session[s].user, username, 128))
885 return s;
886
887 }
888 return 0; // Not found.
889 }
890
891 void send_garp(in_addr_t ip)
892 {
893 int s;
894 struct ifreq ifr;
895 uint8_t mac[6];
896
897 s = socket(PF_INET, SOCK_DGRAM, 0);
898 if (s < 0)
899 {
900 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
901 return;
902 }
903 memset(&ifr, 0, sizeof(ifr));
904 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
905 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
906 {
907 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
908 close(s);
909 return;
910 }
911 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
912 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
913 {
914 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
915 close(s);
916 return;
917 }
918 close(s);
919 sendarp(ifr.ifr_ifindex, mac, ip);
920 }
921
922 static sessiont *sessiontbysessionidt(sessionidt s)
923 {
924 if (!s || s >= MAXSESSION) return NULL;
925 return &session[s];
926 }
927
928 static sessionidt sessionidtbysessiont(sessiont *s)
929 {
930 sessionidt val = s-session;
931 if (s < session || val >= MAXSESSION) return 0;
932 return val;
933 }
934
935 // actually send a control message for a specific tunnel
936 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
937 {
938 struct sockaddr_in addr;
939
940 CSTAT(tunnelsend);
941
942 if (!t)
943 {
944 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
945 STAT(tunnel_tx_errors);
946 return;
947 }
948
949 if (!tunnel[t].ip)
950 {
951 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
952 STAT(tunnel_tx_errors);
953 return;
954 }
955
956 memset(&addr, 0, sizeof(addr));
957 addr.sin_family = AF_INET;
958 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
959 addr.sin_port = htons(tunnel[t].port);
960
961 // sequence expected, if sequence in message
962 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
963
964 // If this is a control message, deal with retries
965 if (*buf & 0x80)
966 {
967 tunnel[t].last = time_now; // control message sent
968 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
969 if (tunnel[t].try)
970 {
971 STAT(tunnel_retries);
972 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
973 }
974 }
975
976 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
977 {
978 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
979 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
980 STAT(tunnel_tx_errors);
981 return;
982 }
983
984 LOG_HEX(5, "Send Tunnel Data", buf, l);
985 STAT(tunnel_tx_packets);
986 INC_STAT(tunnel_tx_bytes, l);
987 }
988
989 //
990 // Tiny helper function to write data to
991 // the 'tun' device.
992 //
993 int tun_write(uint8_t * data, int size)
994 {
995 return write(tunfd, data, size);
996 }
997
998 // adjust tcp mss to avoid fragmentation (called only for tcp packets with syn set)
999 void adjust_tcp_mss(sessionidt s, tunnelidt t, uint8_t *buf, int len, uint8_t *tcp)
1000 {
1001 int d = (tcp[12] >> 4) * 4;
1002 uint8_t *mss = 0;
1003 uint8_t *opts;
1004 uint8_t *data;
1005 uint16_t orig;
1006 uint32_t sum;
1007
1008 if ((tcp[13] & 0x3f) & ~(TCP_FLAG_SYN|TCP_FLAG_ACK)) // only want SYN and SYN,ACK
1009 return;
1010
1011 if (tcp + d > buf + len) // short?
1012 return;
1013
1014 opts = tcp + 20;
1015 data = tcp + d;
1016
1017 while (opts < data)
1018 {
1019 if (*opts == 2 && opts[1] == 4) // mss option (2), length 4
1020 {
1021 mss = opts + 2;
1022 if (mss + 2 > data) return; // short?
1023 break;
1024 }
1025
1026 if (*opts == 0) return; // end of options
1027 if (*opts == 1 || !opts[1]) // no op (one byte), or no length (prevent loop)
1028 opts++;
1029 else
1030 opts += opts[1]; // skip over option
1031 }
1032
1033 if (!mss) return; // not found
1034 orig = ntohs(*(uint16_t *) mss);
1035
1036 if (orig <= MSS) return; // mss OK
1037
1038 LOG(5, s, t, "TCP: %s:%u -> %s:%u SYN%s: adjusted mss from %u to %u\n",
1039 fmtaddr(*(in_addr_t *) (buf + 12), 0), ntohs(*(uint16_t *) tcp),
1040 fmtaddr(*(in_addr_t *) (buf + 16), 1), ntohs(*(uint16_t *) (tcp + 2)),
1041 (tcp[13] & TCP_FLAG_ACK) ? ",ACK" : "", orig, MSS);
1042
1043 // set mss
1044 *(int16_t *) mss = htons(MSS);
1045
1046 // adjust checksum (see rfc1141)
1047 sum = orig + (~MSS & 0xffff);
1048 sum += ntohs(*(uint16_t *) (tcp + 16));
1049 sum = (sum & 0xffff) + (sum >> 16);
1050 *(uint16_t *) (tcp + 16) = htons(sum + (sum >> 16));
1051 }
1052
1053 // process outgoing (to tunnel) IP
1054 //
1055 static void processipout(uint8_t *buf, int len)
1056 {
1057 sessionidt s;
1058 sessiont *sp;
1059 tunnelidt t;
1060 in_addr_t ip;
1061
1062 uint8_t *data = buf; // Keep a copy of the originals.
1063 int size = len;
1064
1065 uint8_t b[MAXETHER + 20];
1066
1067 CSTAT(processipout);
1068
1069 if (len < MIN_IP_SIZE)
1070 {
1071 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
1072 STAT(tun_rx_errors);
1073 return;
1074 }
1075 if (len >= MAXETHER)
1076 {
1077 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
1078 STAT(tun_rx_errors);
1079 return;
1080 }
1081
1082 // Skip the tun header
1083 buf += 4;
1084 len -= 4;
1085
1086 // Got an IP header now
1087 if (*(uint8_t *)(buf) >> 4 != 4)
1088 {
1089 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
1090 return;
1091 }
1092
1093 ip = *(uint32_t *)(buf + 16);
1094 if (!(s = sessionbyip(ip)))
1095 {
1096 // Is this a packet for a session that doesn't exist?
1097 static int rate = 0; // Number of ICMP packets we've sent this second.
1098 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1099
1100 if (last != time_now)
1101 {
1102 last = time_now;
1103 rate = 0;
1104 }
1105
1106 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1107 {
1108 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
1109 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4),
1110 config->bind_address ? config->bind_address : my_address, buf, len);
1111 }
1112 return;
1113 }
1114 t = session[s].tunnel;
1115 sp = &session[s];
1116
1117 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
1118 if (config->max_packets > 0)
1119 {
1120 if (sess_local[s].last_packet_out == TIME)
1121 {
1122 int max = config->max_packets;
1123
1124 // All packets for throttled sessions are handled by the
1125 // master, so further limit by using the throttle rate.
1126 // A bit of a kludge, since throttle rate is in kbps,
1127 // but should still be generous given our average DSL
1128 // packet size is 200 bytes: a limit of 28kbps equates
1129 // to around 180 packets per second.
1130 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
1131 max = sp->throttle_out;
1132
1133 if (++sess_local[s].packets_out > max)
1134 {
1135 sess_local[s].packets_dropped++;
1136 return;
1137 }
1138 }
1139 else
1140 {
1141 if (sess_local[s].packets_dropped)
1142 {
1143 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
1144 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
1145 sess_local[s].packets_dropped, sess_local[s].packets_out,
1146 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
1147 sp->user);
1148 }
1149
1150 sess_local[s].last_packet_out = TIME;
1151 sess_local[s].packets_out = 1;
1152 sess_local[s].packets_dropped = 0;
1153 }
1154 }
1155
1156 // run access-list if any
1157 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
1158 return;
1159
1160 // adjust MSS on SYN and SYN,ACK packets with options
1161 if ((ntohs(*(uint16_t *) (buf + 6)) & 0x1fff) == 0 && buf[9] == IPPROTO_TCP) // first tcp fragment
1162 {
1163 int ihl = (buf[0] & 0xf) * 4; // length of IP header
1164 if (len >= ihl + 20 && (buf[ihl + 13] & TCP_FLAG_SYN) && ((buf[ihl + 12] >> 4) > 5))
1165 adjust_tcp_mss(s, t, buf, len, buf + ihl);
1166 }
1167
1168 if (sp->tbf_out)
1169 {
1170 // Are we throttling this session?
1171 if (config->cluster_iam_master)
1172 tbf_queue_packet(sp->tbf_out, data, size);
1173 else
1174 master_throttle_packet(sp->tbf_out, data, size);
1175 return;
1176 }
1177
1178 if (sp->walled_garden && !config->cluster_iam_master)
1179 {
1180 // We are walled-gardening this
1181 master_garden_packet(s, data, size);
1182 return;
1183 }
1184
1185 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1186
1187 // Add on L2TP header
1188 {
1189 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP);
1190 if (!p) return;
1191 tunnelsend(b, len + (p-b), t); // send it...
1192 }
1193
1194 // Snooping this session, send it to intercept box
1195 if (sp->snoop_ip && sp->snoop_port)
1196 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1197
1198 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1199 sp->cout_delta += len;
1200 sp->pout++;
1201 udp_tx += len;
1202
1203 sess_local[s].cout += len; // To send to master..
1204 sess_local[s].pout++;
1205 }
1206
1207 // process outgoing (to tunnel) IPv6
1208 //
1209 static void processipv6out(uint8_t * buf, int len)
1210 {
1211 sessionidt s;
1212 sessiont *sp;
1213 tunnelidt t;
1214 in_addr_t ip;
1215 struct in6_addr ip6;
1216
1217 uint8_t *data = buf; // Keep a copy of the originals.
1218 int size = len;
1219
1220 uint8_t b[MAXETHER + 20];
1221
1222 CSTAT(processipv6out);
1223
1224 if (len < MIN_IP_SIZE)
1225 {
1226 LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
1227 STAT(tunnel_tx_errors);
1228 return;
1229 }
1230 if (len >= MAXETHER)
1231 {
1232 LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
1233 STAT(tunnel_tx_errors);
1234 return;
1235 }
1236
1237 // Skip the tun header
1238 buf += 4;
1239 len -= 4;
1240
1241 // Got an IP header now
1242 if (*(uint8_t *)(buf) >> 4 != 6)
1243 {
1244 LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
1245 return;
1246 }
1247
1248 ip6 = *(struct in6_addr *)(buf+24);
1249 s = sessionbyipv6(ip6);
1250
1251 if (s == 0)
1252 {
1253 ip = *(uint32_t *)(buf + 32);
1254 s = sessionbyip(ip);
1255 }
1256
1257 if (s == 0)
1258 {
1259 // Is this a packet for a session that doesn't exist?
1260 static int rate = 0; // Number of ICMP packets we've sent this second.
1261 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1262
1263 if (last != time_now)
1264 {
1265 last = time_now;
1266 rate = 0;
1267 }
1268
1269 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1270 {
1271 // FIXME: Should send icmp6 host unreachable
1272 }
1273 return;
1274 }
1275 t = session[s].tunnel;
1276 sp = &session[s];
1277
1278 // FIXME: add DoS prevention/filters?
1279
1280 if (sp->tbf_out)
1281 {
1282 // Are we throttling this session?
1283 if (config->cluster_iam_master)
1284 tbf_queue_packet(sp->tbf_out, data, size);
1285 else
1286 master_throttle_packet(sp->tbf_out, data, size);
1287 return;
1288 }
1289 else if (sp->walled_garden && !config->cluster_iam_master)
1290 {
1291 // We are walled-gardening this
1292 master_garden_packet(s, data, size);
1293 return;
1294 }
1295
1296 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1297
1298 // Add on L2TP header
1299 {
1300 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIPV6);
1301 if (!p) return;
1302 tunnelsend(b, len + (p-b), t); // send it...
1303 }
1304
1305 // Snooping this session, send it to intercept box
1306 if (sp->snoop_ip && sp->snoop_port)
1307 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1308
1309 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1310 sp->cout_delta += len;
1311 sp->pout++;
1312 udp_tx += len;
1313
1314 sess_local[s].cout += len; // To send to master..
1315 sess_local[s].pout++;
1316 }
1317
1318 //
1319 // Helper routine for the TBF filters.
1320 // Used to send queued data in to the user!
1321 //
1322 static void send_ipout(sessionidt s, uint8_t *buf, int len)
1323 {
1324 sessiont *sp;
1325 tunnelidt t;
1326 in_addr_t ip;
1327
1328 uint8_t b[MAXETHER + 20];
1329
1330 if (len < 0 || len > MAXETHER)
1331 {
1332 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
1333 return;
1334 }
1335
1336 // Skip the tun header
1337 buf += 4;
1338 len -= 4;
1339
1340 ip = *(in_addr_t *)(buf + 16);
1341
1342 if (!session[s].ip)
1343 return;
1344
1345 t = session[s].tunnel;
1346 sp = &session[s];
1347
1348 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1349
1350 // Add on L2TP header
1351 {
1352 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP);
1353 if (!p) return;
1354 tunnelsend(b, len + (p-b), t); // send it...
1355 }
1356
1357 // Snooping this session.
1358 if (sp->snoop_ip && sp->snoop_port)
1359 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1360
1361 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1362 sp->cout_delta += len;
1363 sp->pout++;
1364 udp_tx += len;
1365
1366 sess_local[s].cout += len; // To send to master..
1367 sess_local[s].pout++;
1368 }
1369
1370 // add an AVP (16 bit)
1371 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
1372 {
1373 uint16_t l = (m ? 0x8008 : 0x0008);
1374 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1375 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1376 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1377 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
1378 c->length += 8;
1379 }
1380
1381 // add an AVP (32 bit)
1382 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
1383 {
1384 uint16_t l = (m ? 0x800A : 0x000A);
1385 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1386 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1387 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1388 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
1389 c->length += 10;
1390 }
1391
1392 // add an AVP (string)
1393 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
1394 {
1395 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
1396 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1397 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1398 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1399 memcpy(c->buf + c->length + 6, val, strlen(val));
1400 c->length += 6 + strlen(val);
1401 }
1402
1403 // add a binary AVP
1404 static void controlb(controlt * c, uint16_t avp, uint8_t *val, unsigned int len, uint8_t m)
1405 {
1406 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
1407 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1408 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1409 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1410 memcpy(c->buf + c->length + 6, val, len);
1411 c->length += 6 + len;
1412 }
1413
1414 // new control connection
1415 static controlt *controlnew(uint16_t mtype)
1416 {
1417 controlt *c;
1418 if (!controlfree)
1419 c = malloc(sizeof(controlt));
1420 else
1421 {
1422 c = controlfree;
1423 controlfree = c->next;
1424 }
1425 assert(c);
1426 c->next = 0;
1427 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
1428 c->length = 12;
1429 control16(c, 0, mtype, 1);
1430 return c;
1431 }
1432
1433 // send zero block if nothing is waiting
1434 // (ZLB send).
1435 static void controlnull(tunnelidt t)
1436 {
1437 uint8_t buf[12];
1438 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
1439 return;
1440
1441 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
1442 *(uint16_t *) (buf + 2) = htons(12); // length
1443 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
1444 *(uint16_t *) (buf + 6) = htons(0); // session
1445 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
1446 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
1447 tunnelsend(buf, 12, t);
1448 }
1449
1450 // add a control message to a tunnel, and send if within window
1451 static void controladd(controlt *c, sessionidt far, tunnelidt t)
1452 {
1453 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
1454 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
1455 *(uint16_t *) (c->buf + 6) = htons(far); // session
1456 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
1457 tunnel[t].ns++; // advance sequence
1458 // link in message in to queue
1459 if (tunnel[t].controlc)
1460 tunnel[t].controle->next = c;
1461 else
1462 tunnel[t].controls = c;
1463
1464 tunnel[t].controle = c;
1465 tunnel[t].controlc++;
1466
1467 // send now if space in window
1468 if (tunnel[t].controlc <= tunnel[t].window)
1469 {
1470 tunnel[t].try = 0; // first send
1471 tunnelsend(c->buf, c->length, t);
1472 }
1473 }
1474
1475 //
1476 // Throttle or Unthrottle a session
1477 //
1478 // Throttle the data from/to through a session to no more than
1479 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1480 // user).
1481 //
1482 // If either value is -1, the current value is retained for that
1483 // direction.
1484 //
1485 void throttle_session(sessionidt s, int rate_in, int rate_out)
1486 {
1487 if (!session[s].opened)
1488 return; // No-one home.
1489
1490 if (!*session[s].user)
1491 return; // User not logged in
1492
1493 if (rate_in >= 0)
1494 {
1495 int bytes = rate_in * 1024 / 8; // kbits to bytes
1496 if (session[s].tbf_in)
1497 free_tbf(session[s].tbf_in);
1498
1499 if (rate_in > 0)
1500 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1501 else
1502 session[s].tbf_in = 0;
1503
1504 session[s].throttle_in = rate_in;
1505 }
1506
1507 if (rate_out >= 0)
1508 {
1509 int bytes = rate_out * 1024 / 8;
1510 if (session[s].tbf_out)
1511 free_tbf(session[s].tbf_out);
1512
1513 if (rate_out > 0)
1514 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1515 else
1516 session[s].tbf_out = 0;
1517
1518 session[s].throttle_out = rate_out;
1519 }
1520 }
1521
1522 // add/remove filters from session (-1 = no change)
1523 void filter_session(sessionidt s, int filter_in, int filter_out)
1524 {
1525 if (!session[s].opened)
1526 return; // No-one home.
1527
1528 if (!*session[s].user)
1529 return; // User not logged in
1530
1531 // paranoia
1532 if (filter_in > MAXFILTER) filter_in = -1;
1533 if (filter_out > MAXFILTER) filter_out = -1;
1534 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1535 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1536
1537 if (filter_in >= 0)
1538 {
1539 if (session[s].filter_in)
1540 ip_filters[session[s].filter_in - 1].used--;
1541
1542 if (filter_in > 0)
1543 ip_filters[filter_in - 1].used++;
1544
1545 session[s].filter_in = filter_in;
1546 }
1547
1548 if (filter_out >= 0)
1549 {
1550 if (session[s].filter_out)
1551 ip_filters[session[s].filter_out - 1].used--;
1552
1553 if (filter_out > 0)
1554 ip_filters[filter_out - 1].used++;
1555
1556 session[s].filter_out = filter_out;
1557 }
1558 }
1559
1560 // start tidy shutdown of session
1561 void sessionshutdown(sessionidt s, char *reason, int result, int error)
1562 {
1563 int walled_garden = session[s].walled_garden;
1564
1565
1566 CSTAT(sessionshutdown);
1567
1568 if (!session[s].opened)
1569 {
1570 LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
1571 return; // not a live session
1572 }
1573
1574 if (!session[s].die)
1575 {
1576 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1577 LOG(2, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1578 run_plugins(PLUGIN_KILL_SESSION, &data);
1579 }
1580
1581 if (session[s].ip && !walled_garden && !session[s].die)
1582 {
1583 // RADIUS Stop message
1584 uint16_t r = radiusnew(s);
1585 if (r)
1586 {
1587 // stop, if not already trying
1588 if (radius[r].state != RADIUSSTOP)
1589 radiussend(r, RADIUSSTOP);
1590 }
1591 else
1592 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1593
1594 // Save counters to dump to accounting file
1595 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1596 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1597 }
1598
1599 if (session[s].ip)
1600 { // IP allocated, clear and unroute
1601 int r;
1602 int routed = 0;
1603 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1604 {
1605 if ((session[s].ip & session[s].route[r].mask) ==
1606 (session[s].route[r].ip & session[s].route[r].mask))
1607 routed++;
1608
1609 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1610 session[s].route[r].ip = 0;
1611 }
1612
1613 if (session[s].ip_pool_index == -1) // static ip
1614 {
1615 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1616 session[s].ip = 0;
1617 }
1618 else
1619 free_ip_address(s);
1620
1621 // unroute IPv6, if setup
1622 if (session[s].ppp.ipv6cp == Opened && session[s].ipv6prefixlen)
1623 route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
1624 }
1625
1626 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1627 throttle_session(s, 0, 0);
1628
1629 if (result)
1630 { // Send CDN
1631 controlt *c = controlnew(14); // sending CDN
1632 if (error)
1633 {
1634 uint8_t buf[4];
1635 *(uint16_t *) buf = htons(result);
1636 *(uint16_t *) (buf+2) = htons(error);
1637 controlb(c, 1, buf, 4, 1);
1638 }
1639 else
1640 control16(c, 1, result, 1);
1641
1642 control16(c, 14, s, 1); // assigned session (our end)
1643 controladd(c, session[s].far, session[s].tunnel); // send the message
1644 }
1645
1646 if (!session[s].die)
1647 session[s].die = TIME + 150; // Clean up in 15 seconds
1648
1649 // update filter refcounts
1650 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1651 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1652
1653 // clear PPP state
1654 memset(&session[s].ppp, 0, sizeof(session[s].ppp));
1655 sess_local[s].lcp.restart = 0;
1656 sess_local[s].ipcp.restart = 0;
1657 sess_local[s].ipv6cp.restart = 0;
1658 sess_local[s].ccp.restart = 0;
1659
1660 cluster_send_session(s);
1661 }
1662
1663 void sendipcp(sessionidt s, tunnelidt t)
1664 {
1665 uint8_t buf[MAXETHER];
1666 uint8_t *q;
1667
1668 CSTAT(sendipcp);
1669 LOG(3, s, t, "IPCP: send ConfigReq\n");
1670
1671 if (!session[s].unique_id)
1672 {
1673 if (!++last_id) ++last_id; // skip zero
1674 session[s].unique_id = last_id;
1675 }
1676
1677 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPCP);
1678 if (!q) return;
1679
1680 *q = ConfigReq;
1681 q[1] = session[s].unique_id & 0xf; // ID, dont care, we only send one type of request
1682 *(uint16_t *) (q + 2) = htons(10); // packet length
1683 q[4] = 3; // ip address option
1684 q[5] = 6; // option length
1685 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1686 config->bind_address ? config->bind_address :
1687 my_address; // send my IP
1688
1689 tunnelsend(buf, 10 + (q - buf), t); // send it
1690 restart_timer(s, ipcp);
1691 }
1692
1693 void sendipv6cp(sessionidt s, tunnelidt t)
1694 {
1695 uint8_t buf[MAXETHER];
1696 uint8_t *q;
1697
1698 CSTAT(sendipv6cp);
1699 LOG(3, s, t, "IPV6CP: send ConfigReq\n");
1700
1701 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPV6CP);
1702 if (!q) return;
1703
1704 *q = ConfigReq;
1705 q[1] = session[s].unique_id & 0xf; // ID, don't care, we
1706 // only send one type
1707 // of request
1708 *(uint16_t *) (q + 2) = htons(14);
1709 q[4] = 1; // interface identifier option
1710 q[5] = 10; // option length
1711 *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
1712 *(uint32_t *) (q + 10) = 0;
1713 q[13] = 1;
1714
1715 tunnelsend(buf, 14 + (q - buf), t); // send it
1716 restart_timer(s, ipv6cp);
1717 }
1718
1719 static void sessionclear(sessionidt s)
1720 {
1721 memset(&session[s], 0, sizeof(session[s]));
1722 memset(&sess_local[s], 0, sizeof(sess_local[s]));
1723 memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
1724
1725 session[s].tunnel = T_FREE; // Mark it as free.
1726 session[s].next = sessionfree;
1727 sessionfree = s;
1728 }
1729
1730 // kill a session now
1731 void sessionkill(sessionidt s, char *reason)
1732 {
1733
1734 CSTAT(sessionkill);
1735
1736 if (!session[s].opened) // not alive
1737 return;
1738
1739 if (session[s].next)
1740 {
1741 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%d)\n", session[s].next);
1742 return;
1743 }
1744
1745 session[s].die = TIME;
1746 sessionshutdown(s, reason, 3, 0); // close radius/routes, etc.
1747 if (sess_local[s].radius)
1748 radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
1749
1750 LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1751 sessionclear(s);
1752 cluster_send_session(s);
1753 }
1754
1755 static void tunnelclear(tunnelidt t)
1756 {
1757 if (!t) return;
1758 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1759 tunnel[t].state = TUNNELFREE;
1760 }
1761
1762 // kill a tunnel now
1763 static void tunnelkill(tunnelidt t, char *reason)
1764 {
1765 sessionidt s;
1766 controlt *c;
1767
1768 CSTAT(tunnelkill);
1769
1770 tunnel[t].state = TUNNELDIE;
1771
1772 // free control messages
1773 while ((c = tunnel[t].controls))
1774 {
1775 controlt * n = c->next;
1776 tunnel[t].controls = n;
1777 tunnel[t].controlc--;
1778 c->next = controlfree;
1779 controlfree = c;
1780 }
1781 // kill sessions
1782 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1783 if (session[s].tunnel == t)
1784 sessionkill(s, reason);
1785
1786 // free tunnel
1787 tunnelclear(t);
1788 LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
1789 cli_tunnel_actions[t].action = 0;
1790 cluster_send_tunnel(t);
1791 }
1792
1793 // shut down a tunnel cleanly
1794 static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
1795 {
1796 sessionidt s;
1797
1798 CSTAT(tunnelshutdown);
1799
1800 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1801 {
1802 // never set up, can immediately kill
1803 tunnelkill(t, reason);
1804 return;
1805 }
1806 LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1807
1808 // close session
1809 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1810 if (session[s].tunnel == t)
1811 sessionshutdown(s, reason, 0, 0);
1812
1813 tunnel[t].state = TUNNELDIE;
1814 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
1815 cluster_send_tunnel(t);
1816 // TBA - should we wait for sessions to stop?
1817 if (result)
1818 {
1819 controlt *c = controlnew(4); // sending StopCCN
1820 if (error)
1821 {
1822 uint8_t buf[64];
1823 int l = 4;
1824 *(uint16_t *) buf = htons(result);
1825 *(uint16_t *) (buf+2) = htons(error);
1826 if (msg)
1827 {
1828 int m = strlen(msg);
1829 if (m + 4 > sizeof(buf))
1830 m = sizeof(buf) - 4;
1831
1832 memcpy(buf+4, msg, m);
1833 l += m;
1834 }
1835
1836 controlb(c, 1, buf, l, 1);
1837 }
1838 else
1839 control16(c, 1, result, 1);
1840
1841 control16(c, 9, t, 1); // assigned tunnel (our end)
1842 controladd(c, 0, t); // send the message
1843 }
1844 }
1845
1846 // read and process packet on tunnel (UDP)
1847 void processudp(uint8_t *buf, int len, struct sockaddr_in *addr)
1848 {
1849 uint8_t *chapresponse = NULL;
1850 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1851 uint8_t *p = buf + 2;
1852
1853
1854 CSTAT(processudp);
1855
1856 udp_rx += len;
1857 udp_rx_pkt++;
1858 LOG_HEX(5, "UDP Data", buf, len);
1859 STAT(tunnel_rx_packets);
1860 INC_STAT(tunnel_rx_bytes, len);
1861 if (len < 6)
1862 {
1863 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
1864 STAT(tunnel_rx_errors);
1865 return;
1866 }
1867 if ((buf[1] & 0x0F) != 2)
1868 {
1869 LOG(1, 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1870 STAT(tunnel_rx_errors);
1871 return;
1872 }
1873 if (*buf & 0x40)
1874 { // length
1875 l = ntohs(*(uint16_t *) p);
1876 p += 2;
1877 }
1878 t = ntohs(*(uint16_t *) p);
1879 p += 2;
1880 s = ntohs(*(uint16_t *) p);
1881 p += 2;
1882 if (s >= MAXSESSION)
1883 {
1884 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
1885 STAT(tunnel_rx_errors);
1886 return;
1887 }
1888 if (t >= MAXTUNNEL)
1889 {
1890 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
1891 STAT(tunnel_rx_errors);
1892 return;
1893 }
1894 if (*buf & 0x08)
1895 { // ns/nr
1896 ns = ntohs(*(uint16_t *) p);
1897 p += 2;
1898 nr = ntohs(*(uint16_t *) p);
1899 p += 2;
1900 }
1901 if (*buf & 0x02)
1902 { // offset
1903 uint16_t o = ntohs(*(uint16_t *) p);
1904 p += o + 2;
1905 }
1906 if ((p - buf) > l)
1907 {
1908 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
1909 STAT(tunnel_rx_errors);
1910 return;
1911 }
1912 l -= (p - buf);
1913
1914 // used to time out old tunnels
1915 if (t && tunnel[t].state == TUNNELOPEN)
1916 tunnel[t].lastrec = time_now;
1917
1918 if (*buf & 0x80)
1919 { // control
1920 uint16_t message = 0xFFFF; // message type
1921 uint8_t fatal = 0;
1922 uint8_t mandatory = 0;
1923 uint16_t asession = 0; // assigned session
1924 uint32_t amagic = 0; // magic number
1925 uint8_t aflags = 0; // flags from last LCF
1926 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1927 char called[MAXTEL] = ""; // called number
1928 char calling[MAXTEL] = ""; // calling number
1929
1930 if (!config->cluster_iam_master)
1931 {
1932 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1933 return;
1934 }
1935
1936 // control messages must have bits 0x80|0x40|0x08
1937 // (type, length and sequence) set, and bits 0x02|0x01
1938 // (offset and priority) clear
1939 if ((*buf & 0xCB) != 0xC8)
1940 {
1941 LOG(1, s, t, "Bad control header %02X\n", *buf);
1942 STAT(tunnel_rx_errors);
1943 return;
1944 }
1945
1946 // check for duplicate tunnel open message
1947 if (!t && ns == 0)
1948 {
1949 int i;
1950
1951 //
1952 // Is this a duplicate of the first packet? (SCCRQ)
1953 //
1954 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
1955 {
1956 if (tunnel[i].state != TUNNELOPENING ||
1957 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
1958 tunnel[i].port != ntohs(addr->sin_port) )
1959 continue;
1960 t = i;
1961 LOG(3, s, t, "Duplicate SCCRQ?\n");
1962 break;
1963 }
1964 }
1965
1966 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
1967 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1968
1969 // if no tunnel specified, assign one
1970 if (!t)
1971 {
1972 if (!(t = new_tunnel()))
1973 {
1974 LOG(1, 0, 0, "No more tunnels\n");
1975 STAT(tunnel_overflow);
1976 return;
1977 }
1978 tunnelclear(t);
1979 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
1980 tunnel[t].port = ntohs(addr->sin_port);
1981 tunnel[t].window = 4; // default window
1982 STAT(tunnel_created);
1983 LOG(1, 0, t, " New tunnel from %s:%u ID %d\n",
1984 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
1985 }
1986
1987 // If the 'ns' just received is not the 'nr' we're
1988 // expecting, just send an ack and drop it.
1989 //
1990 // if 'ns' is less, then we got a retransmitted packet.
1991 // if 'ns' is greater than missed a packet. Either way
1992 // we should ignore it.
1993 if (ns != tunnel[t].nr)
1994 {
1995 // is this the sequence we were expecting?
1996 STAT(tunnel_rx_errors);
1997 LOG(1, 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n",
1998 t, ns, tunnel[t].nr);
1999
2000 if (l) // Is this not a ZLB?
2001 controlnull(t);
2002 return;
2003 }
2004
2005 // check sequence of this message
2006 {
2007 int skip = tunnel[t].window; // track how many in-window packets are still in queue
2008 // some to clear maybe?
2009 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
2010 {
2011 controlt *c = tunnel[t].controls;
2012 tunnel[t].controls = c->next;
2013 tunnel[t].controlc--;
2014 c->next = controlfree;
2015 controlfree = c;
2016 skip--;
2017 tunnel[t].try = 0; // we have progress
2018 }
2019
2020 // receiver advance (do here so quoted correctly in any sends below)
2021 if (l) tunnel[t].nr = (ns + 1);
2022 if (skip < 0) skip = 0;
2023 if (skip < tunnel[t].controlc)
2024 {
2025 // some control packets can now be sent that were previous stuck out of window
2026 int tosend = tunnel[t].window - skip;
2027 controlt *c = tunnel[t].controls;
2028 while (c && skip)
2029 {
2030 c = c->next;
2031 skip--;
2032 }
2033 while (c && tosend)
2034 {
2035 tunnel[t].try = 0; // first send
2036 tunnelsend(c->buf, c->length, t);
2037 c = c->next;
2038 tosend--;
2039 }
2040 }
2041 if (!tunnel[t].controlc)
2042 tunnel[t].retry = 0; // caught up
2043 }
2044 if (l)
2045 { // if not a null message
2046 int result = 0;
2047 int error = 0;
2048 char *msg = 0;
2049
2050 // process AVPs
2051 while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
2052 {
2053 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
2054 uint8_t *b = p;
2055 uint8_t flags = *p;
2056 uint16_t mtype;
2057 if (n > l)
2058 {
2059 LOG(1, s, t, "Invalid length in AVP\n");
2060 STAT(tunnel_rx_errors);
2061 return;
2062 }
2063 p += n; // next
2064 l -= n;
2065 if (flags & 0x3C) // reserved bits, should be clear
2066 {
2067 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
2068 fatal = flags;
2069 result = 2; // general error
2070 error = 3; // reserved field non-zero
2071 msg = 0;
2072 continue; // next
2073 }
2074 b += 2;
2075 if (*(uint16_t *) (b))
2076 {
2077 LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
2078 fatal = flags;
2079 result = 2; // general error
2080 error = 6; // generic vendor-specific error
2081 msg = "unsupported vendor-specific";
2082 continue; // next
2083 }
2084 b += 2;
2085 mtype = ntohs(*(uint16_t *) (b));
2086 b += 2;
2087 n -= 6;
2088
2089 if (flags & 0x40)
2090 {
2091 uint16_t orig_len;
2092
2093 // handle hidden AVPs
2094 if (!*config->l2tp_secret)
2095 {
2096 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
2097 fatal = flags;
2098 result = 2; // general error
2099 error = 6; // generic vendor-specific error
2100 msg = "secret not specified";
2101 continue;
2102 }
2103 if (!session[s].random_vector_length)
2104 {
2105 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
2106 fatal = flags;
2107 result = 2; // general error
2108 error = 6; // generic
2109 msg = "no random vector";
2110 continue;
2111 }
2112 if (n < 8)
2113 {
2114 LOG(2, s, t, "Short hidden AVP.\n");
2115 fatal = flags;
2116 result = 2; // general error
2117 error = 2; // length is wrong
2118 msg = 0;
2119 continue;
2120 }
2121
2122 // Unhide the AVP
2123 unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
2124
2125 orig_len = ntohs(*(uint16_t *) b);
2126 if (orig_len > n + 2)
2127 {
2128 LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
2129 orig_len, n);
2130
2131 fatal = flags;
2132 result = 2; // general error
2133 error = 2; // length is wrong
2134 msg = 0;
2135 continue;
2136 }
2137
2138 b += 2;
2139 n = orig_len;
2140 }
2141
2142 LOG(4, s, t, " AVP %d (%s) len %d%s%s\n", mtype, l2tp_avp_name(mtype), n,
2143 flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
2144
2145 switch (mtype)
2146 {
2147 case 0: // message type
2148 message = ntohs(*(uint16_t *) b);
2149 mandatory = flags & 0x80;
2150 LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_code(message));
2151 break;
2152 case 1: // result code
2153 {
2154 uint16_t rescode = ntohs(*(uint16_t *) b);
2155 const char* resdesc = "(unknown)";
2156 if (message == 4)
2157 { /* StopCCN */
2158 resdesc = l2tp_stopccn_result_code(rescode);
2159 }
2160 else if (message == 14)
2161 { /* CDN */
2162 resdesc = l2tp_cdn_result_code(rescode);
2163 }
2164
2165 LOG(4, s, t, " Result Code %d: %s\n", rescode, resdesc);
2166 if (n >= 4)
2167 {
2168 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
2169 LOG(4, s, t, " Error Code %d: %s\n", errcode, l2tp_error_code(errcode));
2170 }
2171 if (n > 4)
2172 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
2173
2174 break;
2175 }
2176 break;
2177 case 2: // protocol version
2178 {
2179 version = ntohs(*(uint16_t *) (b));
2180 LOG(4, s, t, " Protocol version = %d\n", version);
2181 if (version && version != 0x0100)
2182 { // allow 0.0 and 1.0
2183 LOG(1, s, t, " Bad protocol version %04X\n", version);
2184 fatal = flags;
2185 result = 5; // unspported protocol version
2186 error = 0x0100; // supported version
2187 msg = 0;
2188 continue; // next
2189 }
2190 }
2191 break;
2192 case 3: // framing capabilities
2193 // LOG(4, s, t, "Framing capabilities\n");
2194 break;
2195 case 4: // bearer capabilities
2196 // LOG(4, s, t, "Bearer capabilities\n");
2197 break;
2198 case 5: // tie breaker
2199 // We never open tunnels, so we don't care about tie breakers
2200 // LOG(4, s, t, "Tie breaker\n");
2201 continue;
2202 case 6: // firmware revision
2203 // LOG(4, s, t, "Firmware revision\n");
2204 break;
2205 case 7: // host name
2206 memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
2207 memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
2208 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
2209 // TBA - to send to RADIUS
2210 break;
2211 case 8: // vendor name
2212 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
2213 memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
2214 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
2215 break;
2216 case 9: // assigned tunnel
2217 tunnel[t].far = ntohs(*(uint16_t *) (b));
2218 LOG(4, s, t, " Remote tunnel id = %d\n", tunnel[t].far);
2219 break;
2220 case 10: // rx window
2221 tunnel[t].window = ntohs(*(uint16_t *) (b));
2222 if (!tunnel[t].window)
2223 tunnel[t].window = 1; // window of 0 is silly
2224 LOG(4, s, t, " rx window = %d\n", tunnel[t].window);
2225 break;
2226 case 11: // Challenge
2227 {
2228 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
2229 build_chap_response(b, 2, n, &chapresponse);
2230 }
2231 break;
2232 case 13: // Response
2233 // Why did they send a response? We never challenge.
2234 LOG(2, s, t, " received unexpected challenge response\n");
2235 break;
2236
2237 case 14: // assigned session
2238 asession = session[s].far = ntohs(*(uint16_t *) (b));
2239 LOG(4, s, t, " assigned session = %d\n", asession);
2240 break;
2241 case 15: // call serial number
2242 LOG(4, s, t, " call serial number = %d\n", ntohl(*(uint32_t *)b));
2243 break;
2244 case 18: // bearer type
2245 LOG(4, s, t, " bearer type = %d\n", ntohl(*(uint32_t *)b));
2246 // TBA - for RADIUS
2247 break;
2248 case 19: // framing type
2249 LOG(4, s, t, " framing type = %d\n", ntohl(*(uint32_t *)b));
2250 // TBA
2251 break;
2252 case 21: // called number
2253 memset(called, 0, sizeof(called));
2254 memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
2255 LOG(4, s, t, " Called <%s>\n", called);
2256 break;
2257 case 22: // calling number
2258 memset(calling, 0, sizeof(calling));
2259 memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
2260 LOG(4, s, t, " Calling <%s>\n", calling);
2261 break;
2262 case 23: // subtype
2263 break;
2264 case 24: // tx connect speed
2265 if (n == 4)
2266 {
2267 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
2268 }
2269 else
2270 {
2271 // AS5300s send connect speed as a string
2272 char tmp[30];
2273 memset(tmp, 0, sizeof(tmp));
2274 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2275 session[s].tx_connect_speed = atol(tmp);
2276 }
2277 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
2278 break;
2279 case 38: // rx connect speed
2280 if (n == 4)
2281 {
2282 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
2283 }
2284 else
2285 {
2286 // AS5300s send connect speed as a string
2287 char tmp[30];
2288 memset(tmp, 0, sizeof(tmp));
2289 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2290 session[s].rx_connect_speed = atol(tmp);
2291 }
2292 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
2293 break;
2294 case 25: // Physical Channel ID
2295 {
2296 uint32_t tmp = ntohl(*(uint32_t *) b);
2297 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
2298 break;
2299 }
2300 case 29: // Proxy Authentication Type
2301 {
2302 uint16_t atype = ntohs(*(uint16_t *)b);
2303 LOG(4, s, t, " Proxy Auth Type %d (%s)\n", atype, ppp_auth_type(atype));
2304 break;
2305 }
2306 case 30: // Proxy Authentication Name
2307 {
2308 char authname[64];
2309 memset(authname, 0, sizeof(authname));
2310 memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
2311 LOG(4, s, t, " Proxy Auth Name (%s)\n",
2312 authname);
2313 break;
2314 }
2315 case 31: // Proxy Authentication Challenge
2316 {
2317 LOG(4, s, t, " Proxy Auth Challenge\n");
2318 break;
2319 }
2320 case 32: // Proxy Authentication ID
2321 {
2322 uint16_t authid = ntohs(*(uint16_t *)(b));
2323 LOG(4, s, t, " Proxy Auth ID (%d)\n", authid);
2324 break;
2325 }
2326 case 33: // Proxy Authentication Response
2327 LOG(4, s, t, " Proxy Auth Response\n");
2328 break;
2329 case 27: // last sent lcp
2330 { // find magic number
2331 uint8_t *p = b, *e = p + n;
2332 while (p + 1 < e && p[1] && p + p[1] <= e)
2333 {
2334 if (*p == 5 && p[1] == 6) // Magic-Number
2335 amagic = ntohl(*(uint32_t *) (p + 2));
2336 else if (*p == 7) // Protocol-Field-Compression
2337 aflags |= SESSION_PFC;
2338 else if (*p == 8) // Address-and-Control-Field-Compression
2339 aflags |= SESSION_ACFC;
2340 p += p[1];
2341 }
2342 }
2343 break;
2344 case 28: // last recv lcp confreq
2345 break;
2346 case 26: // Initial Received LCP CONFREQ
2347 break;
2348 case 39: // seq required - we control it as an LNS anyway...
2349 break;
2350 case 36: // Random Vector
2351 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
2352 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
2353 if (n > sizeof(session[s].random_vector))
2354 n = sizeof(session[s].random_vector);
2355 memcpy(session[s].random_vector, b, n);
2356 session[s].random_vector_length = n;
2357 break;
2358 default:
2359 {
2360 static char e[] = "unknown AVP 0xXXXX";
2361 LOG(2, s, t, " Unknown AVP type %d\n", mtype);
2362 fatal = flags;
2363 result = 2; // general error
2364 error = 8; // unknown mandatory AVP
2365 sprintf((msg = e) + 14, "%04x", mtype);
2366 continue; // next
2367 }
2368 }
2369 }
2370 // process message
2371 if (fatal & 0x80)
2372 tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
2373 else
2374 switch (message)
2375 {
2376 case 1: // SCCRQ - Start Control Connection Request
2377 tunnel[t].state = TUNNELOPENING;
2378 if (main_quit != QUIT_SHUTDOWN)
2379 {
2380 controlt *c = controlnew(2); // sending SCCRP
2381 control16(c, 2, version, 1); // protocol version
2382 control32(c, 3, 3, 1); // framing
2383 controls(c, 7, hostname, 1); // host name
2384 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
2385 control16(c, 9, t, 1); // assigned tunnel
2386 controladd(c, 0, t); // send the resply
2387 }
2388 else
2389 {
2390 tunnelshutdown(t, "Shutting down", 6, 0, 0);
2391 }
2392 break;
2393 case 2: // SCCRP
2394 tunnel[t].state = TUNNELOPEN;
2395 break;
2396 case 3: // SCCN
2397 tunnel[t].state = TUNNELOPEN;
2398 controlnull(t); // ack
2399 break;
2400 case 4: // StopCCN
2401 controlnull(t); // ack
2402 tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
2403 break;
2404 case 6: // HELLO
2405 controlnull(t); // simply ACK
2406 break;
2407 case 7: // OCRQ
2408 // TBA
2409 break;
2410 case 8: // OCRO
2411 // TBA
2412 break;
2413 case 9: // OCCN
2414 // TBA
2415 break;
2416 case 10: // ICRQ
2417 if (sessionfree && main_quit != QUIT_SHUTDOWN)
2418 {
2419 controlt *c = controlnew(11); // ICRP
2420
2421 s = sessionfree;
2422 sessionfree = session[s].next;
2423 memset(&session[s], 0, sizeof(session[s]));
2424
2425 if (s > config->cluster_highest_sessionid)
2426 config->cluster_highest_sessionid = s;
2427
2428 session[s].opened = time_now;
2429 session[s].tunnel = t;
2430 session[s].far = asession;
2431 session[s].last_packet = time_now;
2432 LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
2433 control16(c, 14, s, 1); // assigned session
2434 controladd(c, asession, t); // send the reply
2435
2436 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
2437 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
2438
2439 session[s].ppp.phase = Establish;
2440 session[s].ppp.lcp = Starting;
2441
2442 STAT(session_created);
2443 break;
2444 }
2445
2446 {
2447 controlt *c = controlnew(14); // CDN
2448 if (!sessionfree)
2449 {
2450 STAT(session_overflow);
2451 LOG(1, 0, t, "No free sessions\n");
2452 control16(c, 1, 4, 0); // temporary lack of resources
2453 }
2454 else
2455 control16(c, 1, 2, 7); // shutting down, try another
2456
2457 controladd(c, asession, t); // send the message
2458 }
2459 return;
2460 case 11: // ICRP
2461 // TBA
2462 break;
2463 case 12: // ICCN
2464 if (amagic == 0) amagic = time_now;
2465 session[s].magic = amagic; // set magic number
2466 session[s].flags = aflags; // set flags received
2467 session[s].mru = PPPoE_MRU; // default
2468 controlnull(t); // ack
2469
2470 // start LCP
2471 sess_local[s].lcp_authtype = config->radius_authprefer;
2472 sess_local[s].ppp_mru = MRU;
2473 sendlcp(s, t);
2474 change_state(s, lcp, RequestSent);
2475 break;
2476
2477 case 14: // CDN
2478 controlnull(t); // ack
2479 sessionshutdown(s, "Closed (Received CDN).", 0, 0);
2480 break;
2481 case 0xFFFF:
2482 LOG(1, s, t, "Missing message type\n");
2483 break;
2484 default:
2485 STAT(tunnel_rx_errors);
2486 if (mandatory)
2487 tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
2488 else
2489 LOG(1, s, t, "Unknown message type %d\n", message);
2490 break;
2491 }
2492 if (chapresponse) free(chapresponse);
2493 cluster_send_tunnel(t);
2494 }
2495 else
2496 {
2497 LOG(4, s, t, " Got a ZLB ack\n");
2498 }
2499 }
2500 else
2501 { // data
2502 uint16_t proto;
2503
2504 LOG_HEX(5, "Receive Tunnel Data", p, l);
2505 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
2506 { // HDLC address header, discard
2507 p += 2;
2508 l -= 2;
2509 }
2510 if (l < 2)
2511 {
2512 LOG(1, s, t, "Short ppp length %d\n", l);
2513 STAT(tunnel_rx_errors);
2514 return;
2515 }
2516 if (*p & 1)
2517 {
2518 proto = *p++;
2519 l--;
2520 }
2521 else
2522 {
2523 proto = ntohs(*(uint16_t *) p);
2524 p += 2;
2525 l -= 2;
2526 }
2527
2528 if (s && !session[s].opened) // Is something wrong??
2529 {
2530 if (!config->cluster_iam_master)
2531 {
2532 // Pass it off to the master to deal with..
2533 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2534 return;
2535 }
2536
2537
2538 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
2539 STAT(tunnel_rx_errors);
2540 return;
2541 }
2542
2543 if (proto == PPPPAP)
2544 {
2545 session[s].last_packet = time_now;
2546 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2547 processpap(s, t, p, l);
2548 }
2549 else if (proto == PPPCHAP)
2550 {
2551 session[s].last_packet = time_now;
2552 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2553 processchap(s, t, p, l);
2554 }
2555 else if (proto == PPPLCP)
2556 {
2557 session[s].last_packet = time_now;
2558 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2559 processlcp(s, t, p, l);
2560 }
2561 else if (proto == PPPIPCP)
2562 {
2563 session[s].last_packet = time_now;
2564 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2565 processipcp(s, t, p, l);
2566 }
2567 else if (proto == PPPIPV6CP && config->ipv6_prefix.s6_addr[0])
2568 {
2569 session[s].last_packet = time_now;
2570 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2571 processipv6cp(s, t, p, l);
2572 }
2573 else if (proto == PPPCCP)
2574 {
2575 session[s].last_packet = time_now;
2576 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2577 processccp(s, t, p, l);
2578 }
2579 else if (proto == PPPIP)
2580 {
2581 if (session[s].die)
2582 {
2583 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2584 return; // closing session, PPP not processed
2585 }
2586
2587 session[s].last_packet = time_now;
2588 if (session[s].walled_garden && !config->cluster_iam_master)
2589 {
2590 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2591 return;
2592 }
2593
2594 processipin(s, t, p, l);
2595 }
2596 else if (proto == PPPIPV6 && config->ipv6_prefix.s6_addr[0])
2597 {
2598 if (session[s].die)
2599 {
2600 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2601 return; // closing session, PPP not processed
2602 }
2603
2604 session[s].last_packet = time_now;
2605 if (session[s].walled_garden && !config->cluster_iam_master)
2606 {
2607 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2608 return;
2609 }
2610
2611 processipv6in(s, t, p, l);
2612 }
2613 else if (session[s].ppp.lcp == Opened)
2614 {
2615 session[s].last_packet = time_now;
2616 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2617 protoreject(s, t, p, l, proto);
2618 }
2619 else
2620 {
2621 LOG(2, s, t, "Unknown PPP protocol 0x%04X received in LCP %s state\n",
2622 proto, ppp_state(session[s].ppp.lcp));
2623 }
2624 }
2625 }
2626
2627 // read and process packet on tun
2628 static void processtun(uint8_t * buf, int len)
2629 {
2630 LOG_HEX(5, "Receive TUN Data", buf, len);
2631 STAT(tun_rx_packets);
2632 INC_STAT(tun_rx_bytes, len);
2633
2634 CSTAT(processtun);
2635
2636 eth_rx_pkt++;
2637 eth_rx += len;
2638 if (len < 22)
2639 {
2640 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2641 STAT(tun_rx_errors);
2642 return;
2643 }
2644
2645 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
2646 processipout(buf, len);
2647 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
2648 && config->ipv6_prefix.s6_addr[0])
2649 processipv6out(buf, len);
2650
2651 // Else discard.
2652 }
2653
2654 // Handle retries, timeouts. Runs every 1/10th sec, want to ensure
2655 // that we look at the whole of the tunnel, radius and session tables
2656 // every second
2657 static void regular_cleanups(double period)
2658 {
2659 // Next tunnel, radius and session to check for actions on.
2660 static tunnelidt t = 0;
2661 static int r = 0;
2662 static sessionidt s = 0;
2663
2664 int t_actions = 0;
2665 int r_actions = 0;
2666 int s_actions = 0;
2667
2668 int t_slice;
2669 int r_slice;
2670 int s_slice;
2671
2672 int i;
2673 int a;
2674
2675 // divide up tables into slices based on the last run
2676 t_slice = config->cluster_highest_tunnelid * period;
2677 r_slice = (MAXRADIUS - 1) * period;
2678 s_slice = config->cluster_highest_sessionid * period;
2679
2680 if (t_slice < 1)
2681 t_slice = 1;
2682 else if (t_slice > config->cluster_highest_tunnelid)
2683 t_slice = config->cluster_highest_tunnelid;
2684
2685 if (r_slice < 1)
2686 r_slice = 1;
2687 else if (r_slice > (MAXRADIUS - 1))
2688 r_slice = MAXRADIUS - 1;
2689
2690 if (s_slice < 1)
2691 s_slice = 1;
2692 else if (s_slice > config->cluster_highest_sessionid)
2693 s_slice = config->cluster_highest_sessionid;
2694
2695 LOG(4, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
2696
2697 for (i = 0; i < t_slice; i++)
2698 {
2699 t++;
2700 if (t > config->cluster_highest_tunnelid)
2701 t = 1;
2702
2703 // check for expired tunnels
2704 if (tunnel[t].die && tunnel[t].die <= TIME)
2705 {
2706 STAT(tunnel_timeout);
2707 tunnelkill(t, "Expired");
2708 t_actions++;
2709 continue;
2710 }
2711 // check for message resend
2712 if (tunnel[t].retry && tunnel[t].controlc)
2713 {
2714 // resend pending messages as timeout on reply
2715 if (tunnel[t].retry <= TIME)
2716 {
2717 controlt *c = tunnel[t].controls;
2718 uint8_t w = tunnel[t].window;
2719 tunnel[t].try++; // another try
2720 if (tunnel[t].try > 5)
2721 tunnelkill(t, "Timeout on control message"); // game over
2722 else
2723 while (c && w--)
2724 {
2725 tunnelsend(c->buf, c->length, t);
2726 c = c->next;
2727 }
2728
2729 t_actions++;
2730 }
2731 }
2732 // Send hello
2733 if (tunnel[t].state == TUNNELOPEN && !tunnel[t].controlc && (time_now - tunnel[t].lastrec) > 60)
2734 {
2735 controlt *c = controlnew(6); // sending HELLO
2736 controladd(c, 0, t); // send the message
2737 LOG(3, 0, t, "Sending HELLO message\n");
2738 t_actions++;
2739 }
2740
2741 // Check for tunnel changes requested from the CLI
2742 if ((a = cli_tunnel_actions[t].action))
2743 {
2744 cli_tunnel_actions[t].action = 0;
2745 if (a & CLI_TUN_KILL)
2746 {
2747 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2748 tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
2749 t_actions++;
2750 }
2751 }
2752 }
2753
2754 for (i = 0; i < r_slice; i++)
2755 {
2756 r++;
2757 if (r >= MAXRADIUS)
2758 r = 1;
2759
2760 if (!radius[r].state)
2761 continue;
2762
2763 if (radius[r].retry <= TIME)
2764 {
2765 radiusretry(r);
2766 r_actions++;
2767 }
2768 }
2769
2770 for (i = 0; i < s_slice; i++)
2771 {
2772 s++;
2773 if (s > config->cluster_highest_sessionid)
2774 s = 1;
2775
2776 if (!session[s].opened) // Session isn't in use
2777 continue;
2778
2779 // check for expired sessions
2780 if (session[s].die)
2781 {
2782 if (session[s].die <= TIME)
2783 {
2784 sessionkill(s, "Expired");
2785 s_actions++;
2786 }
2787 continue;
2788 }
2789
2790 // PPP timeouts
2791 if (sess_local[s].lcp.restart <= time_now)
2792 {
2793 int next_state = session[s].ppp.lcp;
2794 switch (session[s].ppp.lcp)
2795 {
2796 case RequestSent:
2797 case AckReceived:
2798 next_state = RequestSent;
2799
2800 case AckSent:
2801 if (sess_local[s].lcp.conf_sent < config->ppp_max_configure)
2802 {
2803 LOG(3, s, session[s].tunnel, "No ACK for LCP ConfigReq... resending\n");
2804 sendlcp(s, session[s].tunnel);
2805 change_state(s, lcp, next_state);
2806 }
2807 else
2808 {
2809 sessionshutdown(s, "No response to LCP ConfigReq.", 3, 0);
2810 STAT(session_timeout);
2811 }
2812
2813 s_actions++;
2814 }
2815
2816 if (session[s].die)
2817 continue;
2818 }
2819
2820 if (sess_local[s].ipcp.restart <= time_now)
2821 {
2822 int next_state = session[s].ppp.ipcp;
2823 switch (session[s].ppp.ipcp)
2824 {
2825 case RequestSent:
2826 case AckReceived:
2827 next_state = RequestSent;
2828
2829 case AckSent:
2830 if (sess_local[s].ipcp.conf_sent < config->ppp_max_configure)
2831 {
2832 LOG(3, s, session[s].tunnel, "No ACK for IPCP ConfigReq... resending\n");
2833 sendipcp(s, session[s].tunnel);
2834 change_state(s, ipcp, next_state);
2835 }
2836 else
2837 {
2838 sessionshutdown(s, "No response to IPCP ConfigReq.", 3, 0);
2839 STAT(session_timeout);
2840 }
2841
2842 s_actions++;
2843 }
2844
2845 if (session[s].die)
2846 continue;
2847 }
2848
2849 if (sess_local[s].ipv6cp.restart <= time_now)
2850 {
2851 int next_state = session[s].ppp.ipv6cp;
2852 switch (session[s].ppp.ipv6cp)
2853 {
2854 case RequestSent:
2855 case AckReceived:
2856 next_state = RequestSent;
2857
2858 case AckSent:
2859 if (sess_local[s].ipv6cp.conf_sent < config->ppp_max_configure)
2860 {
2861 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq... resending\n");
2862 sendipv6cp(s, session[s].tunnel);
2863 change_state(s, ipv6cp, next_state);
2864 }
2865 else
2866 {
2867 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq\n");
2868 change_state(s, ipv6cp, Stopped);
2869 }
2870
2871 s_actions++;
2872 }
2873 }
2874
2875 if (sess_local[s].ccp.restart <= time_now)
2876 {
2877 int next_state = session[s].ppp.ccp;
2878 switch (session[s].ppp.ccp)
2879 {
2880 case RequestSent:
2881 case AckReceived:
2882 next_state = RequestSent;
2883
2884 case AckSent:
2885 if (sess_local[s].ccp.conf_sent < config->ppp_max_configure)
2886 {
2887 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq... resending\n");
2888 sendccp(s, session[s].tunnel);
2889 change_state(s, ccp, next_state);
2890 }
2891 else
2892 {
2893 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq\n");
2894 change_state(s, ccp, Stopped);
2895 }
2896
2897 s_actions++;
2898 }
2899 }
2900
2901 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2902 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2903 {
2904 sessionshutdown(s, "No response to LCP ECHO requests.", 3, 0);
2905 STAT(session_timeout);
2906 s_actions++;
2907 continue;
2908 }
2909
2910 // No data in ECHO_TIMEOUT seconds, send LCP ECHO
2911 if (session[s].ppp.phase >= Establish && (time_now - session[s].last_packet >= ECHO_TIMEOUT) &&
2912 (time_now - sess_local[s].last_echo >= ECHO_TIMEOUT))
2913 {
2914 uint8_t b[MAXETHER];
2915
2916 uint8_t *q = makeppp(b, sizeof(b), 0, 0, s, session[s].tunnel, PPPLCP);
2917 if (!q) continue;
2918
2919 *q = EchoReq;
2920 *(uint8_t *)(q + 1) = (time_now % 255); // ID
2921 *(uint16_t *)(q + 2) = htons(8); // Length
2922 *(uint32_t *)(q + 4) = session[s].ppp.lcp == Opened ? htonl(session[s].magic) : 0; // Magic Number
2923
2924 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2925 (int)(time_now - session[s].last_packet));
2926 tunnelsend(b, 24, session[s].tunnel); // send it
2927 sess_local[s].last_echo = time_now;
2928 s_actions++;
2929 }
2930
2931 // Check for actions requested from the CLI
2932 if ((a = cli_session_actions[s].action))
2933 {
2934 int send = 0;
2935
2936 cli_session_actions[s].action = 0;
2937 if (a & CLI_SESS_KILL)
2938 {
2939 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
2940 sessionshutdown(s, "Requested by administrator.", 3, 0);
2941 a = 0; // dead, no need to check for other actions
2942 s_actions++;
2943 }
2944
2945 if (a & CLI_SESS_NOSNOOP)
2946 {
2947 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
2948 session[s].snoop_ip = 0;
2949 session[s].snoop_port = 0;
2950 s_actions++;
2951 send++;
2952 }
2953 else if (a & CLI_SESS_SNOOP)
2954 {
2955 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2956 fmtaddr(cli_session_actions[s].snoop_ip, 0),
2957 cli_session_actions[s].snoop_port);
2958
2959 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2960 session[s].snoop_port = cli_session_actions[s].snoop_port;
2961 s_actions++;
2962 send++;
2963 }
2964
2965 if (a & CLI_SESS_NOTHROTTLE)
2966 {
2967 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
2968 throttle_session(s, 0, 0);
2969 s_actions++;
2970 send++;
2971 }
2972 else if (a & CLI_SESS_THROTTLE)
2973 {
2974 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
2975 cli_session_actions[s].throttle_in,
2976 cli_session_actions[s].throttle_out);
2977
2978 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
2979 s_actions++;
2980 send++;
2981 }
2982
2983 if (a & CLI_SESS_NOFILTER)
2984 {
2985 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
2986 filter_session(s, 0, 0);
2987 s_actions++;
2988 send++;
2989 }
2990 else if (a & CLI_SESS_FILTER)
2991 {
2992 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
2993 cli_session_actions[s].filter_in,
2994 cli_session_actions[s].filter_out);
2995
2996 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
2997 s_actions++;
2998 send++;
2999 }
3000
3001 if (send)
3002 cluster_send_session(s);
3003 }
3004
3005 // RADIUS interim accounting
3006 if (config->radius_accounting && config->radius_interim > 0
3007 && session[s].ip && !session[s].walled_garden
3008 && !sess_local[s].radius // RADIUS already in progress
3009 && time_now - sess_local[s].last_interim >= config->radius_interim)
3010 {
3011 int rad = radiusnew(s);
3012 if (!rad)
3013 {
3014 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
3015 STAT(radius_overflow);
3016 continue;
3017 }
3018
3019 LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
3020 session[s].user, session[s].unique_id);
3021
3022 radiussend(rad, RADIUSINTERIM);
3023 sess_local[s].last_interim = time_now;
3024 s_actions++;
3025 }
3026 }
3027
3028 LOG(4, 0, 0, "End regular cleanup: checked %d/%d/%d tunnels/radius/sessions; %d/%d/%d actions\n",
3029 t_slice, r_slice, s_slice, t_actions, r_actions, s_actions);
3030 }
3031
3032 //
3033 // Are we in the middle of a tunnel update, or radius
3034 // requests??
3035 //
3036 static int still_busy(void)
3037 {
3038 int i;
3039 static clockt last_talked = 0;
3040 static clockt start_busy_wait = 0;
3041
3042 if (!config->cluster_iam_master)
3043 {
3044 #ifdef BGP
3045 static time_t stopped_bgp = 0;
3046 if (bgp_configured)
3047 {
3048 if (!stopped_bgp)
3049 {
3050 LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
3051
3052 for (i = 0; i < BGP_NUM_PEERS; i++)
3053 if (bgp_peers[i].state == Established)
3054 bgp_stop(&bgp_peers[i]);
3055
3056 stopped_bgp = time_now;
3057
3058 // we don't want to become master
3059 cluster_send_ping(0);
3060
3061 return 1;
3062 }
3063
3064 if (time_now < (stopped_bgp + QUIT_DELAY))
3065 return 1;
3066 }
3067 #endif /* BGP */
3068
3069 return 0;
3070 }
3071
3072 if (main_quit == QUIT_SHUTDOWN)
3073 {
3074 static int dropped = 0;
3075 if (!dropped)
3076 {
3077 int i;
3078
3079 LOG(1, 0, 0, "Dropping sessions and tunnels\n");
3080 for (i = 1; i < MAXTUNNEL; i++)
3081 if (tunnel[i].ip || tunnel[i].state)
3082 tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
3083
3084 dropped = 1;
3085 }
3086 }
3087
3088 if (start_busy_wait == 0)
3089 start_busy_wait = TIME;
3090
3091 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
3092 {
3093 if (!tunnel[i].controlc)
3094 continue;
3095
3096 if (last_talked != TIME)
3097 {
3098 LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
3099 last_talked = TIME;
3100 }
3101 return 1;
3102 }
3103
3104 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
3105 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
3106 {
3107 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
3108 return 0;
3109 }
3110
3111 for (i = 1; i < MAXRADIUS; i++)
3112 {
3113 if (radius[i].state == RADIUSNULL)
3114 continue;
3115 if (radius[i].state == RADIUSWAIT)
3116 continue;
3117
3118 if (last_talked != TIME)
3119 {
3120 LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
3121 last_talked = TIME;
3122 }
3123 return 1;
3124 }
3125
3126 return 0;
3127 }
3128
3129 #ifdef HAVE_EPOLL
3130 # include <sys/epoll.h>
3131 #else
3132 # define FAKE_EPOLL_IMPLEMENTATION /* include the functions */
3133 # include "fake_epoll.h"
3134 #endif
3135
3136 // the base set of fds polled: cli, cluster, tun, udp, control, dae
3137 #define BASE_FDS 6
3138
3139 // additional polled fds
3140 #ifdef BGP
3141 # define EXTRA_FDS BGP_NUM_PEERS
3142 #else
3143 # define EXTRA_FDS 0
3144 #endif
3145
3146 // main loop - gets packets on tun or udp and processes them
3147 static void mainloop(void)
3148 {
3149 int i;
3150 uint8_t buf[65536];
3151 clockt next_cluster_ping = 0; // send initial ping immediately
3152 struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
3153 int maxevent = sizeof(events)/sizeof(*events);
3154
3155 if ((epollfd = epoll_create(maxevent)) < 0)
3156 {
3157 LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
3158 exit(1);
3159 }
3160
3161 LOG(4, 0, 0, "Beginning of main loop. clifd=%d, cluster_sockfd=%d, tunfd=%d, udpfd=%d, controlfd=%d, daefd=%d\n",
3162 clifd, cluster_sockfd, tunfd, udpfd, controlfd, daefd);
3163
3164 /* setup our fds to poll for input */
3165 {
3166 static struct event_data d[BASE_FDS];
3167 struct epoll_event e;
3168
3169 e.events = EPOLLIN;
3170 i = 0;
3171
3172 d[i].type = FD_TYPE_CLI;
3173 e.data.ptr = &d[i++];
3174 epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
3175
3176 d[i].type = FD_TYPE_CLUSTER;
3177 e.data.ptr = &d[i++];
3178 epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &e);
3179
3180 d[i].type = FD_TYPE_TUN;
3181 e.data.ptr = &d[i++];
3182 epoll_ctl(epollfd, EPOLL_CTL_ADD, tunfd, &e);
3183
3184 d[i].type = FD_TYPE_UDP;
3185 e.data.ptr = &d[i++];
3186 epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd, &e);
3187
3188 d[i].type = FD_TYPE_CONTROL;
3189 e.data.ptr = &d[i++];
3190 epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
3191
3192 d[i].type = FD_TYPE_DAE;
3193 e.data.ptr = &d[i++];
3194 epoll_ctl(epollfd, EPOLL_CTL_ADD, daefd, &e);
3195 }
3196
3197 #ifdef BGP
3198 signal(SIGPIPE, SIG_IGN);
3199 bgp_setup(config->as_number);
3200 if (config->bind_address)
3201 bgp_add_route(config->bind_address, 0xffffffff);
3202
3203 for (i = 0; i < BGP_NUM_PEERS; i++)
3204 {
3205 if (config->neighbour[i].name[0])
3206 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3207 config->neighbour[i].as, config->neighbour[i].keepalive,
3208 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3209 }
3210 #endif /* BGP */
3211
3212 while (!main_quit || still_busy())
3213 {
3214 int more = 0;
3215 int n;
3216
3217
3218 if (main_reload)
3219 {
3220 main_reload = 0;
3221 read_config_file();
3222 config->reload_config++;
3223 }
3224
3225 if (config->reload_config)
3226 {
3227 config->reload_config = 0;
3228 update_config();
3229 }
3230
3231 #ifdef BGP
3232 bgp_set_poll();
3233 #endif /* BGP */
3234
3235 n = epoll_wait(epollfd, events, maxevent, 100); // timeout 100ms (1/10th sec)
3236 STAT(select_called);
3237
3238 TIME = now(NULL);
3239 if (n < 0)
3240 {
3241 if (errno == EINTR ||
3242 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
3243 continue;
3244
3245 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
3246 break; // exit
3247 }
3248
3249 if (n)
3250 {
3251 struct sockaddr_in addr;
3252 struct in_addr local;
3253 socklen_t alen;
3254 int c, s;
3255 int udp_ready = 0;
3256 int tun_ready = 0;
3257 int cluster_ready = 0;
3258 int udp_pkts = 0;
3259 int tun_pkts = 0;
3260 int cluster_pkts = 0;
3261 #ifdef BGP
3262 uint32_t bgp_events[BGP_NUM_PEERS];
3263 memset(bgp_events, 0, sizeof(bgp_events));
3264 #endif /* BGP */
3265
3266 for (c = n, i = 0; i < c; i++)
3267 {
3268 struct event_data *d = events[i].data.ptr;
3269
3270 switch (d->type)
3271 {
3272 case FD_TYPE_CLI: // CLI connections
3273 {
3274 int cli;
3275
3276 alen = sizeof(addr);
3277 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
3278 {
3279 cli_do(cli);
3280 close(cli);
3281 }
3282 else
3283 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
3284
3285 n--;
3286 break;
3287 }
3288
3289 // these are handled below, with multiple interleaved reads
3290 case FD_TYPE_CLUSTER: cluster_ready++; break;
3291 case FD_TYPE_TUN: tun_ready++; break;
3292 case FD_TYPE_UDP: udp_ready++; break;
3293
3294 case FD_TYPE_CONTROL: // nsctl commands
3295 alen = sizeof(addr);
3296 s = recvfromto(controlfd, buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen, &local);
3297 if (s > 0) processcontrol(buf, s, &addr, alen, &local);
3298 n--;
3299 break;
3300
3301 case FD_TYPE_DAE: // DAE requests
3302 alen = sizeof(addr);
3303 s = recvfrom(daefd, buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen);
3304 if (s > 0) processdae(buf, s, &addr, alen);
3305 n--;
3306 break;
3307
3308 case FD_TYPE_RADIUS: // RADIUS response
3309 alen = sizeof(addr);
3310 s = recvfrom(radfds[d->index], buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen);
3311 if (s >= 0 && config->cluster_iam_master)
3312 {
3313 if (addr.sin_addr.s_addr == config->radiusserver[0] ||
3314 addr.sin_addr.s_addr == config->radiusserver[1])
3315 processrad(buf, s, d->index);
3316 else
3317 LOG(3, 0, 0, "Dropping RADIUS packet from unknown source %s\n",
3318 fmtaddr(addr.sin_addr.s_addr, 0));
3319 }
3320
3321 n--;
3322 break;
3323
3324 #ifdef BGP
3325 case FD_TYPE_BGP:
3326 bgp_events[d->index] = events[i].events;
3327 n--;
3328 break;
3329 #endif /* BGP */
3330
3331 default:
3332 LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
3333 }
3334 }
3335
3336 #ifdef BGP
3337 bgp_process(bgp_events);
3338 #endif /* BGP */
3339
3340 for (c = 0; n && c < config->multi_read_count; c++)
3341 {
3342 // L2TP
3343 if (udp_ready)
3344 {
3345 alen = sizeof(addr);
3346 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
3347 {
3348 processudp(buf, s, &addr);
3349 udp_pkts++;
3350 }
3351 else
3352 {
3353 udp_ready = 0;
3354 n--;
3355 }
3356 }
3357
3358 // incoming IP
3359 if (tun_ready)
3360 {
3361 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
3362 {
3363 processtun(buf, s);
3364 tun_pkts++;
3365 }
3366 else
3367 {
3368 tun_ready = 0;
3369 n--;
3370 }
3371 }
3372
3373 // cluster
3374 if (cluster_ready)
3375 {
3376 alen = sizeof(addr);
3377 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
3378 {
3379 processcluster(buf, s, addr.sin_addr.s_addr);
3380 cluster_pkts++;
3381 }
3382 else
3383 {
3384 cluster_ready = 0;
3385 n--;
3386 }
3387 }
3388 }
3389
3390 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
3391 STAT(multi_read_used);
3392
3393 if (c >= config->multi_read_count)
3394 {
3395 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
3396 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
3397
3398 STAT(multi_read_exceeded);
3399 more++;
3400 }
3401 }
3402
3403 if (time_changed)
3404 {
3405 double Mbps = 1024.0 * 1024.0 / 8 * time_changed;
3406
3407 // Log current traffic stats
3408 snprintf(config->bandwidth, sizeof(config->bandwidth),
3409 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
3410 (udp_rx / Mbps), (eth_tx / Mbps), (eth_rx / Mbps), (udp_tx / Mbps),
3411 ((udp_tx + udp_rx + eth_tx + eth_rx) / Mbps),
3412 udp_rx_pkt / time_changed, eth_rx_pkt / time_changed);
3413
3414 udp_tx = udp_rx = 0;
3415 udp_rx_pkt = eth_rx_pkt = 0;
3416 eth_tx = eth_rx = 0;
3417 time_changed = 0;
3418
3419 if (config->dump_speed)
3420 printf("%s\n", config->bandwidth);
3421
3422 // Update the internal time counter
3423 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3424
3425 {
3426 // Run timer hooks
3427 struct param_timer p = { time_now };
3428 run_plugins(PLUGIN_TIMER, &p);
3429 }
3430 }
3431
3432 // Runs on every machine (master and slaves).
3433 if (next_cluster_ping <= TIME)
3434 {
3435 // Check to see which of the cluster is still alive..
3436
3437 cluster_send_ping(basetime); // Only does anything if we're a slave
3438 cluster_check_master(); // ditto.
3439
3440 cluster_heartbeat(); // Only does anything if we're a master.
3441 cluster_check_slaves(); // ditto.
3442
3443 master_update_counts(); // If we're a slave, send our byte counters to our master.
3444
3445 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
3446 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
3447 else
3448 next_cluster_ping = TIME + config->cluster_hb_interval;
3449 }
3450
3451 if (!config->cluster_iam_master)
3452 continue;
3453
3454 // Run token bucket filtering queue..
3455 // Only run it every 1/10th of a second.
3456 {
3457 static clockt last_run = 0;
3458 if (last_run != TIME)
3459 {
3460 last_run = TIME;
3461 tbf_run_timer();
3462 }
3463 }
3464
3465 // Handle timeouts, retries etc.
3466 {
3467 static double last_clean = 0;
3468 double this_clean;
3469 double diff;
3470
3471 TIME = now(&this_clean);
3472 diff = this_clean - last_clean;
3473
3474 // Run during idle time (after we've handled
3475 // all incoming packets) or every 1/10th sec
3476 if (!more || diff > 0.1)
3477 {
3478 regular_cleanups(diff);
3479 last_clean = this_clean;
3480 }
3481 }
3482
3483 if (*config->accounting_dir)
3484 {
3485 static clockt next_acct = 0;
3486 static clockt next_shut_acct = 0;
3487
3488 if (next_acct <= TIME)
3489 {
3490 // Dump accounting data
3491 next_acct = TIME + ACCT_TIME;
3492 next_shut_acct = TIME + ACCT_SHUT_TIME;
3493 dump_acct_info(1);
3494 }
3495 else if (next_shut_acct <= TIME)
3496 {
3497 // Dump accounting data for shutdown sessions
3498 next_shut_acct = TIME + ACCT_SHUT_TIME;
3499 if (shut_acct_n)
3500 dump_acct_info(0);
3501 }
3502 }
3503 }
3504
3505 // Are we the master and shutting down??
3506 if (config->cluster_iam_master)
3507 cluster_heartbeat(); // Flush any queued changes..
3508
3509 // Ok. Notify everyone we're shutting down. If we're
3510 // the master, this will force an election.
3511 cluster_send_ping(0);
3512
3513 //
3514 // Important!!! We MUST not process any packets past this point!
3515 LOG(1, 0, 0, "Shutdown complete\n");
3516 }
3517
3518 static void stripdomain(char *host)
3519 {
3520 char *p;
3521
3522 if ((p = strchr(host, '.')))
3523 {
3524 char *domain = 0;
3525 char _domain[1024];
3526
3527 // strip off domain
3528 FILE *resolv = fopen("/etc/resolv.conf", "r");
3529 if (resolv)
3530 {
3531 char buf[1024];
3532 char *b;
3533
3534 while (fgets(buf, sizeof(buf), resolv))
3535 {
3536 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
3537 continue;
3538
3539 if (!isspace(buf[6]))
3540 continue;
3541
3542 b = buf + 7;
3543 while (isspace(*b)) b++;
3544
3545 if (*b)
3546 {
3547 char *d = b;
3548 while (*b && !isspace(*b)) b++;
3549 *b = 0;
3550 if (buf[0] == 'd') // domain is canonical
3551 {
3552 domain = d;
3553 break;
3554 }
3555
3556 // first search line
3557 if (!domain)
3558 {
3559 // hold, may be subsequent domain line
3560 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
3561 domain = _domain;
3562 }
3563 }
3564 }
3565
3566 fclose(resolv);
3567 }
3568
3569 if (domain)
3570 {
3571 int hl = strlen(host);
3572 int dl = strlen(domain);
3573 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
3574 host[hl -dl - 1] = 0;
3575 }
3576 else
3577 {
3578 *p = 0; // everything after first dot
3579 }
3580 }
3581 }
3582
3583 // Init data structures
3584 static void initdata(int optdebug, char *optconfig)
3585 {
3586 int i;
3587
3588 if (!(config = shared_malloc(sizeof(configt))))
3589 {
3590 fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
3591 exit(1);
3592 }
3593
3594 memset(config, 0, sizeof(configt));
3595 time(&config->start_time);
3596 strncpy(config->config_file, optconfig, strlen(optconfig));
3597 config->debug = optdebug;
3598 config->num_tbfs = MAXTBFS;
3599 config->rl_rate = 28; // 28kbps
3600 config->cluster_mcast_ttl = 1;
3601 config->cluster_master_min_adv = 1;
3602 config->ppp_restart_time = 3;
3603 config->ppp_max_configure = 10;
3604 config->ppp_max_failure = 5;
3605 strcpy(config->random_device, RANDOMDEVICE);
3606
3607 log_stream = stderr;
3608
3609 #ifdef RINGBUFFER
3610 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
3611 {
3612 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
3613 exit(1);
3614 }
3615 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
3616 #endif
3617
3618 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
3619 {
3620 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
3621 exit(1);
3622 }
3623 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
3624 {
3625 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
3626 exit(1);
3627 }
3628 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
3629 {
3630 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
3631 exit(1);
3632 }
3633
3634 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
3635 {
3636 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
3637 exit(1);
3638 }
3639
3640 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
3641 {
3642 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
3643 exit(1);
3644 }
3645
3646 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
3647 {
3648 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
3649 exit(1);
3650 }
3651
3652 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
3653 {
3654 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
3655 exit(1);
3656 }
3657 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
3658
3659 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
3660 {
3661 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
3662 exit(1);
3663 }
3664 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
3665
3666 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
3667 {
3668 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
3669 exit(1);
3670 }
3671 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
3672
3673 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
3674 memset(session, 0, sizeof(sessiont) * MAXSESSION);
3675 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
3676 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
3677
3678 // Put all the sessions on the free list marked as undefined.
3679 for (i = 1; i < MAXSESSION; i++)
3680 {
3681 session[i].next = i + 1;
3682 session[i].tunnel = T_UNDEF; // mark it as not filled in.
3683 }
3684 session[MAXSESSION - 1].next = 0;
3685 sessionfree = 1;
3686
3687 // Mark all the tunnels as undefined (waiting to be filled in by a download).
3688 for (i = 1; i < MAXTUNNEL; i++)
3689 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
3690
3691 if (!*hostname)
3692 {
3693 // Grab my hostname unless it's been specified
3694 gethostname(hostname, sizeof(hostname));
3695 stripdomain(hostname);
3696 }
3697
3698 _statistics->start_time = _statistics->last_reset = time(NULL);
3699
3700 #ifdef BGP
3701 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
3702 {
3703 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
3704 exit(1);
3705 }
3706 #endif /* BGP */
3707 }
3708
3709 static int assign_ip_address(sessionidt s)
3710 {
3711 uint32_t i;
3712 int best = -1;
3713 time_t best_time = time_now;
3714 char *u = session[s].user;
3715 char reuse = 0;
3716
3717
3718 CSTAT(assign_ip_address);
3719
3720 for (i = 1; i < ip_pool_size; i++)
3721 {
3722 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
3723 continue;
3724
3725 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
3726 {
3727 best = i;
3728 reuse = 1;
3729 break;
3730 }
3731
3732 if (ip_address_pool[i].last < best_time)
3733 {
3734 best = i;
3735 if (!(best_time = ip_address_pool[i].last))
3736 break; // never used, grab this one
3737 }
3738 }
3739
3740 if (best < 0)
3741 {
3742 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
3743 return 0;
3744 }
3745
3746 session[s].ip = ip_address_pool[best].address;
3747 session[s].ip_pool_index = best;
3748 ip_address_pool[best].assigned = 1;
3749 ip_address_pool[best].last = time_now;
3750 ip_address_pool[best].session = s;
3751 if (session[s].walled_garden)
3752 /* Don't track addresses of users in walled garden (note: this
3753 means that their address isn't "sticky" even if they get
3754 un-gardened). */
3755 ip_address_pool[best].user[0] = 0;
3756 else
3757 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
3758
3759 STAT(ip_allocated);
3760 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
3761 reuse ? "Reusing" : "Allocating", best);
3762
3763 return 1;
3764 }
3765
3766 static void free_ip_address(sessionidt s)
3767 {
3768 int i = session[s].ip_pool_index;
3769
3770
3771 CSTAT(free_ip_address);
3772
3773 if (!session[s].ip)
3774 return; // what the?
3775
3776 if (i < 0) // Is this actually part of the ip pool?
3777 i = 0;
3778
3779 STAT(ip_freed);
3780 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
3781 session[s].ip = 0;
3782 ip_address_pool[i].assigned = 0;
3783 ip_address_pool[i].session = 0;
3784 ip_address_pool[i].last = time_now;
3785 }
3786
3787 //
3788 // Fsck the address pool against the session table.
3789 // Normally only called when we become a master.
3790 //
3791 // This isn't perfect: We aren't keep tracking of which
3792 // users used to have an IP address.
3793 //
3794 void rebuild_address_pool(void)
3795 {
3796 int i;
3797
3798 //
3799 // Zero the IP pool allocation, and build
3800 // a map from IP address to pool index.
3801 for (i = 1; i < MAXIPPOOL; ++i)
3802 {
3803 ip_address_pool[i].assigned = 0;
3804 ip_address_pool[i].session = 0;
3805 if (!ip_address_pool[i].address)
3806 continue;
3807
3808 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
3809 }
3810
3811 for (i = 0; i < MAXSESSION; ++i)
3812 {
3813 int ipid;
3814 if (!(session[i].opened && session[i].ip))
3815 continue;
3816
3817 ipid = - lookup_ipmap(htonl(session[i].ip));
3818
3819 if (session[i].ip_pool_index < 0)
3820 {
3821 // Not allocated out of the pool.
3822 if (ipid < 1) // Not found in the pool either? good.
3823 continue;
3824
3825 LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
3826 i, fmtaddr(session[i].ip, 0), ipid);
3827
3828 // Fall through and process it as part of the pool.
3829 }
3830
3831
3832 if (ipid > MAXIPPOOL || ipid < 0)
3833 {
3834 LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
3835 ipid = -1;
3836 session[i].ip_pool_index = ipid;
3837 continue;
3838 }
3839
3840 ip_address_pool[ipid].assigned = 1;
3841 ip_address_pool[ipid].session = i;
3842 ip_address_pool[ipid].last = time_now;
3843 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
3844 session[i].ip_pool_index = ipid;
3845 cache_ipmap(session[i].ip, i); // Fix the ip map.
3846 }
3847 }
3848
3849 //
3850 // Fix the address pool to match a changed session.
3851 // (usually when the master sends us an update).
3852 static void fix_address_pool(int sid)
3853 {
3854 int ipid;
3855
3856 ipid = session[sid].ip_pool_index;
3857
3858 if (ipid > ip_pool_size)
3859 return; // Ignore it. rebuild_address_pool will fix it up.
3860
3861 if (ip_address_pool[ipid].address != session[sid].ip)
3862 return; // Just ignore it. rebuild_address_pool will take care of it.
3863
3864 ip_address_pool[ipid].assigned = 1;
3865 ip_address_pool[ipid].session = sid;
3866 ip_address_pool[ipid].last = time_now;
3867 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
3868 }
3869
3870 //
3871 // Add a block of addresses to the IP pool to hand out.
3872 //
3873 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
3874 {
3875 int i;
3876 if (mask == 0)
3877 mask = 0xffffffff; // Host route only.
3878
3879 addr &= mask;
3880
3881 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
3882 return ;
3883
3884 for (i = addr ;(i & mask) == addr; ++i)
3885 {
3886 if ((i & 0xff) == 0 || (i&0xff) == 255)
3887 continue; // Skip 0 and broadcast addresses.
3888
3889 ip_address_pool[ip_pool_size].address = i;
3890 ip_address_pool[ip_pool_size].assigned = 0;
3891 ++ip_pool_size;
3892 if (ip_pool_size >= MAXIPPOOL)
3893 {
3894 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
3895 return;
3896 }
3897 }
3898 }
3899
3900 // Initialize the IP address pool
3901 static void initippool()
3902 {
3903 FILE *f;
3904 char *p;
3905 char buf[4096];
3906 memset(ip_address_pool, 0, sizeof(ip_address_pool));
3907
3908 if (!(f = fopen(IPPOOLFILE, "r")))
3909 {
3910 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
3911 exit(1);
3912 }
3913
3914 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
3915 {
3916 char *pool = buf;
3917 buf[4095] = 0; // Force it to be zero terminated/
3918
3919 if (*buf == '#' || *buf == '\n')
3920 continue; // Skip comments / blank lines
3921 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
3922 if ((p = (char *)strchr(buf, ':')))
3923 {
3924 in_addr_t src;
3925 *p = '\0';
3926 src = inet_addr(buf);
3927 if (src == INADDR_NONE)
3928 {
3929 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
3930 exit(1);
3931 }
3932 // This entry is for a specific IP only
3933 if (src != config->bind_address)
3934 continue;
3935 *p = ':';
3936 pool = p+1;
3937 }
3938 if ((p = (char *)strchr(pool, '/')))
3939 {
3940 // It's a range
3941 int numbits = 0;
3942 in_addr_t start = 0, mask = 0;
3943
3944 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
3945 *p++ = 0;
3946 if (!*p || !(numbits = atoi(p)))
3947 {
3948 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
3949 continue;
3950 }
3951 start = ntohl(inet_addr(pool));
3952 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
3953
3954 // Add a static route for this pool
3955 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
3956 fmtaddr(htonl(start), 0), 32 + mask);
3957
3958 routeset(0, start, mask, 0, 1);
3959
3960 add_to_ip_pool(start, mask);
3961 }
3962 else
3963 {
3964 // It's a single ip address
3965 add_to_ip_pool(ntohl(inet_addr(pool)), 0);
3966 }
3967 }
3968 fclose(f);
3969 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
3970 }
3971
3972 void snoop_send_packet(uint8_t *packet, uint16_t size, in_addr_t destination, uint16_t port)
3973 {
3974 struct sockaddr_in snoop_addr = {0};
3975 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
3976 return;
3977
3978 snoop_addr.sin_family = AF_INET;
3979 snoop_addr.sin_addr.s_addr = destination;
3980 snoop_addr.sin_port = ntohs(port);
3981
3982 LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", size,
3983 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
3984 htons(snoop_addr.sin_port));
3985
3986 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
3987 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
3988
3989 STAT(packets_snooped);
3990 }
3991
3992 static int dump_session(FILE **f, sessiont *s)
3993 {
3994 if (!s->opened || !s->ip || !(s->cin_delta || s->cout_delta) || !*s->user || s->walled_garden)
3995 return 1;
3996
3997 if (!*f)
3998 {
3999 char filename[1024];
4000 char timestr[64];
4001 time_t now = time(NULL);
4002
4003 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
4004 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
4005
4006 if (!(*f = fopen(filename, "w")))
4007 {
4008 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
4009 return 0;
4010 }
4011
4012 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
4013 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
4014 "# host: %s\n"
4015 "# endpoint: %s\n"
4016 "# time: %ld\n"
4017 "# uptime: %ld\n"
4018 "# format: username ip qos uptxoctets downrxoctets\n",
4019 hostname,
4020 fmtaddr(config->bind_address ? config->bind_address : my_address, 0),
4021 now,
4022 now - basetime);
4023 }
4024
4025 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
4026 fprintf(*f, "%s %s %d %u %u\n",
4027 s->user, // username
4028 fmtaddr(htonl(s->ip), 0), // ip
4029 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
4030 (uint32_t) s->cin_delta, // uptxoctets
4031 (uint32_t) s->cout_delta); // downrxoctets
4032
4033 s->cin_delta = s->cout_delta = 0;
4034
4035 return 1;
4036 }
4037
4038 static void dump_acct_info(int all)
4039 {
4040 int i;
4041 FILE *f = NULL;
4042
4043
4044 CSTAT(dump_acct_info);
4045
4046 if (shut_acct_n)
4047 {
4048 for (i = 0; i < shut_acct_n; i++)
4049 dump_session(&f, &shut_acct[i]);
4050
4051 shut_acct_n = 0;
4052 }
4053
4054 if (all)
4055 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4056 dump_session(&f, &session[i]);
4057
4058 if (f)
4059 fclose(f);
4060 }
4061
4062 // Main program
4063 int main(int argc, char *argv[])
4064 {
4065 int i;
4066 int optdebug = 0;
4067 char *optconfig = CONFIGFILE;
4068
4069 time(&basetime); // start clock
4070
4071 // scan args
4072 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
4073 {
4074 switch (i)
4075 {
4076 case 'd':
4077 if (fork()) exit(0);
4078 setsid();
4079 freopen("/dev/null", "r", stdin);
4080 freopen("/dev/null", "w", stdout);
4081 freopen("/dev/null", "w", stderr);
4082 break;
4083 case 'v':
4084 optdebug++;
4085 break;
4086 case 'c':
4087 optconfig = optarg;
4088 break;
4089 case 'h':
4090 snprintf(hostname, sizeof(hostname), "%s", optarg);
4091 break;
4092 default:
4093 printf("Args are:\n"
4094 "\t-d\t\tDetach from terminal\n"
4095 "\t-c <file>\tConfig file\n"
4096 "\t-h <hostname>\tForce hostname\n"
4097 "\t-v\t\tDebug\n");
4098
4099 return (0);
4100 break;
4101 }
4102 }
4103
4104 // Start the timer routine off
4105 time(&time_now);
4106 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4107
4108 initplugins();
4109 initdata(optdebug, optconfig);
4110
4111 init_cli(hostname);
4112 read_config_file();
4113 update_config();
4114 init_tbf(config->num_tbfs);
4115
4116 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
4117 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
4118 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
4119 {
4120 struct rlimit rlim;
4121 rlim.rlim_cur = RLIM_INFINITY;
4122 rlim.rlim_max = RLIM_INFINITY;
4123 // Remove the maximum core size
4124 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
4125 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
4126
4127 // Make core dumps go to /tmp
4128 chdir("/tmp");
4129 }
4130
4131 if (config->scheduler_fifo)
4132 {
4133 int ret;
4134 struct sched_param params = {0};
4135 params.sched_priority = 1;
4136
4137 if (get_nprocs() < 2)
4138 {
4139 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
4140 config->scheduler_fifo = 0;
4141 }
4142 else
4143 {
4144 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
4145 {
4146 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
4147 }
4148 else
4149 {
4150 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
4151 config->scheduler_fifo = 0;
4152 }
4153 }
4154 }
4155
4156 /* Set up the cluster communications port. */
4157 if (cluster_init() < 0)
4158 exit(1);
4159
4160 inittun();
4161 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
4162
4163 initudp();
4164 initrad();
4165 initippool();
4166
4167 // seed prng
4168 {
4169 unsigned seed = time_now ^ getpid();
4170 LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
4171 srand(seed);
4172 }
4173
4174 signal(SIGHUP, sighup_handler);
4175 signal(SIGCHLD, sigchild_handler);
4176 signal(SIGTERM, shutdown_handler);
4177 signal(SIGINT, shutdown_handler);
4178 signal(SIGQUIT, shutdown_handler);
4179
4180 // Prevent us from getting paged out
4181 if (config->lock_pages)
4182 {
4183 if (!mlockall(MCL_CURRENT))
4184 LOG(1, 0, 0, "Locking pages into memory\n");
4185 else
4186 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
4187 }
4188
4189 // Drop privileges here
4190 if (config->target_uid > 0 && geteuid() == 0)
4191 setuid(config->target_uid);
4192
4193 mainloop();
4194
4195 /* remove plugins (so cleanup code gets run) */
4196 plugins_done();
4197
4198 // Remove the PID file if we wrote it
4199 if (config->wrote_pid && *config->pid_file == '/')
4200 unlink(config->pid_file);
4201
4202 /* kill CLI children */
4203 signal(SIGTERM, SIG_IGN);
4204 kill(0, SIGTERM);
4205 return 0;
4206 }
4207
4208 static void sighup_handler(int sig)
4209 {
4210 main_reload++;
4211 }
4212
4213 static void shutdown_handler(int sig)
4214 {
4215 main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
4216 }
4217
4218 static void sigchild_handler(int sig)
4219 {
4220 while (waitpid(-1, NULL, WNOHANG) > 0)
4221 ;
4222 }
4223
4224 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response)
4225 {
4226 MD5_CTX ctx;
4227 *challenge_response = NULL;
4228
4229 if (!*config->l2tp_secret)
4230 {
4231 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
4232 return;
4233 }
4234
4235 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
4236
4237 *challenge_response = calloc(17, 1);
4238
4239 MD5_Init(&ctx);
4240 MD5_Update(&ctx, &id, 1);
4241 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
4242 MD5_Update(&ctx, challenge, challenge_length);
4243 MD5_Final(*challenge_response, &ctx);
4244
4245 return;
4246 }
4247
4248 static int facility_value(char *name)
4249 {
4250 int i;
4251 for (i = 0; facilitynames[i].c_name; i++)
4252 {
4253 if (strcmp(facilitynames[i].c_name, name) == 0)
4254 return facilitynames[i].c_val;
4255 }
4256 return 0;
4257 }
4258
4259 static void update_config()
4260 {
4261 int i;
4262 char *p;
4263 static int timeout = 0;
4264 static int interval = 0;
4265
4266 // Update logging
4267 closelog();
4268 syslog_log = 0;
4269 if (log_stream)
4270 {
4271 if (log_stream != stderr)
4272 fclose(log_stream);
4273
4274 log_stream = NULL;
4275 }
4276
4277 if (*config->log_filename)
4278 {
4279 if (strstr(config->log_filename, "syslog:") == config->log_filename)
4280 {
4281 char *p = config->log_filename + 7;
4282 if (*p)
4283 {
4284 openlog("l2tpns", LOG_PID, facility_value(p));
4285 syslog_log = 1;
4286 }
4287 }
4288 else if (strchr(config->log_filename, '/') == config->log_filename)
4289 {
4290 if ((log_stream = fopen((char *)(config->log_filename), "a")))
4291 {
4292 fseek(log_stream, 0, SEEK_END);
4293 setbuf(log_stream, NULL);
4294 }
4295 else
4296 {
4297 log_stream = stderr;
4298 setbuf(log_stream, NULL);
4299 }
4300 }
4301 }
4302 else
4303 {
4304 log_stream = stderr;
4305 setbuf(log_stream, NULL);
4306 }
4307
4308 #define L2TP_HDRS (20+8+6+4) // L2TP data encaptulation: ip + udp + l2tp (data) + ppp (inc hdlc)
4309 #define TCP_HDRS (20+20) // TCP encapsulation: ip + tcp
4310
4311 if (config->l2tp_mtu <= 0) config->l2tp_mtu = 1500; // ethernet default
4312 else if (config->l2tp_mtu < MINMTU) config->l2tp_mtu = MINMTU;
4313 else if (config->l2tp_mtu > MAXMTU) config->l2tp_mtu = MAXMTU;
4314
4315 // reset MRU/MSS globals
4316 MRU = config->l2tp_mtu - L2TP_HDRS;
4317 if (MRU > PPPoE_MRU)
4318 MRU = PPPoE_MRU;
4319
4320 MSS = MRU - TCP_HDRS;
4321
4322 // Update radius
4323 config->numradiusservers = 0;
4324 for (i = 0; i < MAXRADSERVER; i++)
4325 if (config->radiusserver[i])
4326 {
4327 config->numradiusservers++;
4328 // Set radius port: if not set, take the port from the
4329 // first radius server. For the first radius server,
4330 // take the #defined default value from l2tpns.h
4331
4332 // test twice, In case someone works with
4333 // a secondary radius server without defining
4334 // a primary one, this will work even then.
4335 if (i > 0 && !config->radiusport[i])
4336 config->radiusport[i] = config->radiusport[i-1];
4337 if (!config->radiusport[i])
4338 config->radiusport[i] = RADPORT;
4339 }
4340
4341 if (!config->numradiusservers)
4342 LOG(0, 0, 0, "No RADIUS servers defined!\n");
4343
4344 // parse radius_authtypes_s
4345 config->radius_authtypes = config->radius_authprefer = 0;
4346 p = config->radius_authtypes_s;
4347 while (p && *p)
4348 {
4349 char *s = strpbrk(p, " \t,");
4350 int type = 0;
4351
4352 if (s)
4353 {
4354 *s++ = 0;
4355 while (*s == ' ' || *s == '\t')
4356 s++;
4357
4358 if (!*s)
4359 s = 0;
4360 }
4361
4362 if (!strncasecmp("chap", p, strlen(p)))
4363 type = AUTHCHAP;
4364 else if (!strncasecmp("pap", p, strlen(p)))
4365 type = AUTHPAP;
4366 else
4367 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
4368
4369 config->radius_authtypes |= type;
4370 if (!config->radius_authprefer)
4371 config->radius_authprefer = type;
4372
4373 p = s;
4374 }
4375
4376 if (!config->radius_authtypes)
4377 {
4378 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
4379 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
4380 }
4381
4382 // normalise radius_authtypes_s
4383 if (config->radius_authprefer == AUTHPAP)
4384 {
4385 strcpy(config->radius_authtypes_s, "pap");
4386 if (config->radius_authtypes & AUTHCHAP)
4387 strcat(config->radius_authtypes_s, ", chap");
4388 }
4389 else
4390 {
4391 strcpy(config->radius_authtypes_s, "chap");
4392 if (config->radius_authtypes & AUTHPAP)
4393 strcat(config->radius_authtypes_s, ", pap");
4394 }
4395
4396 if (!config->radius_dae_port)
4397 config->radius_dae_port = DAEPORT;
4398
4399 // re-initialise the random number source
4400 initrandom(config->random_device);
4401
4402 // Update plugins
4403 for (i = 0; i < MAXPLUGINS; i++)
4404 {
4405 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
4406 continue;
4407
4408 if (*config->plugins[i])
4409 {
4410 // Plugin added
4411 add_plugin(config->plugins[i]);
4412 }
4413 else if (*config->old_plugins[i])
4414 {
4415 // Plugin removed
4416 remove_plugin(config->old_plugins[i]);
4417 }
4418 }
4419
4420 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
4421 if (!config->multi_read_count) config->multi_read_count = 10;
4422 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
4423 if (!*config->cluster_interface)
4424 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
4425
4426 if (!config->cluster_hb_interval)
4427 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
4428
4429 if (!config->cluster_hb_timeout)
4430 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
4431
4432 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
4433 {
4434 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
4435 // late, ensure we're sufficiently larger than that
4436 int t = 4 * config->cluster_hb_interval + 11;
4437
4438 if (config->cluster_hb_timeout < t)
4439 {
4440 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
4441 config->cluster_hb_timeout = t;
4442 }
4443
4444 // Push timing changes to the slaves immediately if we're the master
4445 if (config->cluster_iam_master)
4446 cluster_heartbeat();
4447
4448 interval = config->cluster_hb_interval;
4449 timeout = config->cluster_hb_timeout;
4450 }
4451
4452 // Write PID file
4453 if (*config->pid_file == '/' && !config->wrote_pid)
4454 {
4455 FILE *f;
4456 if ((f = fopen(config->pid_file, "w")))
4457 {
4458 fprintf(f, "%d\n", getpid());
4459 fclose(f);
4460 config->wrote_pid = 1;
4461 }
4462 else
4463 {
4464 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
4465 }
4466 }
4467 }
4468
4469 static void read_config_file()
4470 {
4471 FILE *f;
4472
4473 if (!config->config_file) return;
4474 if (!(f = fopen(config->config_file, "r")))
4475 {
4476 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
4477 return;
4478 }
4479
4480 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
4481 cli_do_file(f);
4482 LOG(3, 0, 0, "Done reading config file\n");
4483 fclose(f);
4484 }
4485
4486 int sessionsetup(sessionidt s, tunnelidt t)
4487 {
4488 // A session now exists, set it up
4489 in_addr_t ip;
4490 char *user;
4491 sessionidt i;
4492 int r;
4493
4494 CSTAT(sessionsetup);
4495
4496 LOG(3, s, t, "Doing session setup for session\n");
4497
4498 if (!session[s].ip)
4499 {
4500 assign_ip_address(s);
4501 if (!session[s].ip)
4502 {
4503 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
4504 sessionshutdown(s, "No IP addresses available.", 2, 7); // try another
4505 return 0;
4506 }
4507 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
4508 fmtaddr(htonl(session[s].ip), 0));
4509 }
4510
4511
4512 // Make sure this is right
4513 session[s].tunnel = t;
4514
4515 // zap old sessions with same IP and/or username
4516 // Don't kill gardened sessions - doing so leads to a DoS
4517 // from someone who doesn't need to know the password
4518 {
4519 ip = session[s].ip;
4520 user = session[s].user;
4521 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4522 {
4523 if (i == s) continue;
4524 if (!session[s].opened) continue;
4525 if (ip == session[i].ip)
4526 {
4527 sessionkill(i, "Duplicate IP address");
4528 continue;
4529 }
4530
4531 if (config->allow_duplicate_users) continue;
4532 if (session[s].walled_garden || session[i].walled_garden) continue;
4533 if (!strcasecmp(user, session[i].user))
4534 sessionkill(i, "Duplicate session for users");
4535 }
4536 }
4537
4538 {
4539 int routed = 0;
4540
4541 // Add the route for this session.
4542 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
4543 {
4544 if ((session[s].ip & session[s].route[r].mask) ==
4545 (session[s].route[r].ip & session[s].route[r].mask))
4546 routed++;
4547
4548 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
4549 }
4550
4551 // Static IPs need to be routed if not already
4552 // convered by a Framed-Route. Anything else is part
4553 // of the IP address pool and is already routed, it
4554 // just needs to be added to the IP cache.
4555 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
4556 if (session[s].ip_pool_index == -1) // static ip
4557 {
4558 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
4559 }
4560 else
4561 cache_ipmap(session[s].ip, s);
4562 }
4563
4564 sess_local[s].lcp_authtype = 0; // RADIUS authentication complete
4565 lcp_open(s, t); // transition to Network phase and send initial IPCP
4566
4567 // Run the plugin's against this new session.
4568 {
4569 struct param_new_session data = { &tunnel[t], &session[s] };
4570 run_plugins(PLUGIN_NEW_SESSION, &data);
4571 }
4572
4573 // Allocate TBFs if throttled
4574 if (session[s].throttle_in || session[s].throttle_out)
4575 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
4576
4577 session[s].last_packet = time_now;
4578
4579 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
4580 fmtaddr(htonl(session[s].ip), 0),
4581 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
4582
4583 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
4584
4585 return 1; // RADIUS OK and IP allocated, done...
4586 }
4587
4588 //
4589 // This session just got dropped on us by the master or something.
4590 // Make sure our tables up up to date...
4591 //
4592 int load_session(sessionidt s, sessiont *new)
4593 {
4594 int i;
4595 int newip = 0;
4596
4597 // Sanity checks.
4598 if (new->ip_pool_index >= MAXIPPOOL ||
4599 new->tunnel >= MAXTUNNEL)
4600 {
4601 LOG(0, s, 0, "Strange session update received!\n");
4602 // FIXME! What to do here?
4603 return 0;
4604 }
4605
4606 //
4607 // Ok. All sanity checks passed. Now we're committed to
4608 // loading the new session.
4609 //
4610
4611 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
4612
4613 // See if routes/ip cache need updating
4614 if (new->ip != session[s].ip)
4615 newip++;
4616
4617 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
4618 if (new->route[i].ip != session[s].route[i].ip ||
4619 new->route[i].mask != session[s].route[i].mask)
4620 newip++;
4621
4622 // needs update
4623 if (newip)
4624 {
4625 int routed = 0;
4626
4627 // remove old routes...
4628 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
4629 {
4630 if ((session[s].ip & session[s].route[i].mask) ==
4631 (session[s].route[i].ip & session[s].route[i].mask))
4632 routed++;
4633
4634 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
4635 }
4636
4637 // ...ip
4638 if (session[s].ip)
4639 {
4640 if (session[s].ip_pool_index == -1) // static IP
4641 {
4642 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
4643 }
4644 else // It's part of the IP pool, remove it manually.
4645 uncache_ipmap(session[s].ip);
4646 }
4647
4648 routed = 0;
4649
4650 // add new routes...
4651 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
4652 {
4653 if ((new->ip & new->route[i].mask) ==
4654 (new->route[i].ip & new->route[i].mask))
4655 routed++;
4656
4657 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
4658 }
4659
4660 // ...ip
4661 if (new->ip)
4662 {
4663 // If there's a new one, add it.
4664 if (new->ip_pool_index == -1)
4665 {
4666 if (!routed) routeset(s, new->ip, 0, 0, 1);
4667 }
4668 else
4669 cache_ipmap(new->ip, s);
4670 }
4671 }
4672
4673 // check v6 routing
4674 if (new->ipv6prefixlen && new->ppp.ipv6cp == Opened && session[s].ppp.ipv6cp != Opened)
4675 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
4676
4677 // check filters
4678 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
4679 {
4680 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
4681 new->filter_in = 0;
4682 }
4683
4684 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
4685 {
4686 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
4687 new->filter_out = 0;
4688 }
4689
4690 if (new->filter_in != session[s].filter_in)
4691 {
4692 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
4693 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
4694 }
4695
4696 if (new->filter_out != session[s].filter_out)
4697 {
4698 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
4699 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
4700 }
4701
4702 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
4703 // for walking the sessions to forward byte counts to the master.
4704 config->cluster_highest_sessionid = s;
4705
4706 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
4707
4708 // Do fixups into address pool.
4709 if (new->ip_pool_index != -1)
4710 fix_address_pool(s);
4711
4712 return 1;
4713 }
4714
4715 static void initplugins()
4716 {
4717 int i;
4718
4719 loaded_plugins = ll_init();
4720 // Initialize the plugins to nothing
4721 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
4722 plugins[i] = ll_init();
4723 }
4724
4725 static void *open_plugin(char *plugin_name, int load)
4726 {
4727 char path[256] = "";
4728
4729 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
4730 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
4731 return dlopen(path, RTLD_NOW);
4732 }
4733
4734 // plugin callback to get a config value
4735 static void *getconfig(char *key, enum config_typet type)
4736 {
4737 int i;
4738
4739 for (i = 0; config_values[i].key; i++)
4740 {
4741 if (!strcmp(config_values[i].key, key))
4742 {
4743 if (config_values[i].type == type)
4744 return ((void *) config) + config_values[i].offset;
4745
4746 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
4747 key, type, config_values[i].type);
4748
4749 return 0;
4750 }
4751 }
4752
4753 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
4754 return 0;
4755 }
4756
4757 static int add_plugin(char *plugin_name)
4758 {
4759 static struct pluginfuncs funcs = {
4760 _log,
4761 _log_hex,
4762 fmtaddr,
4763 sessionbyuser,
4764 sessiontbysessionidt,
4765 sessionidtbysessiont,
4766 radiusnew,
4767 radiussend,
4768 getconfig,
4769 sessionshutdown,
4770 sessionkill,
4771 throttle_session,
4772 cluster_send_session,
4773 };
4774
4775 void *p = open_plugin(plugin_name, 1);
4776 int (*initfunc)(struct pluginfuncs *);
4777 int i;
4778
4779 if (!p)
4780 {
4781 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
4782 return -1;
4783 }
4784
4785 if (ll_contains(loaded_plugins, p))
4786 {
4787 dlclose(p);
4788 return 0; // already loaded
4789 }
4790
4791 {
4792 int *v = dlsym(p, "plugin_api_version");
4793 if (!v || *v != PLUGIN_API_VERSION)
4794 {
4795 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
4796 dlclose(p);
4797 return -1;
4798 }
4799 }
4800
4801 if ((initfunc = dlsym(p, "plugin_init")))
4802 {
4803 if (!initfunc(&funcs))
4804 {
4805 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
4806 dlclose(p);
4807 return -1;
4808 }
4809 }
4810
4811 ll_push(loaded_plugins, p);
4812
4813 for (i = 0; i < max_plugin_functions; i++)
4814 {
4815 void *x;
4816 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4817 {
4818 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
4819 ll_push(plugins[i], x);
4820 }
4821 }
4822
4823 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
4824 return 1;
4825 }
4826
4827 static void run_plugin_done(void *plugin)
4828 {
4829 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
4830
4831 if (donefunc)
4832 donefunc();
4833 }
4834
4835 static int remove_plugin(char *plugin_name)
4836 {
4837 void *p = open_plugin(plugin_name, 0);
4838 int loaded = 0;
4839
4840 if (!p)
4841 return -1;
4842
4843 if (ll_contains(loaded_plugins, p))
4844 {
4845 int i;
4846 for (i = 0; i < max_plugin_functions; i++)
4847 {
4848 void *x;
4849 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4850 ll_delete(plugins[i], x);
4851 }
4852
4853 ll_delete(loaded_plugins, p);
4854 run_plugin_done(p);
4855 loaded = 1;
4856 }
4857
4858 dlclose(p);
4859 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
4860 return loaded;
4861 }
4862
4863 int run_plugins(int plugin_type, void *data)
4864 {
4865 int (*func)(void *data);
4866
4867 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
4868 return PLUGIN_RET_ERROR;
4869
4870 ll_reset(plugins[plugin_type]);
4871 while ((func = ll_next(plugins[plugin_type])))
4872 {
4873 int r = func(data);
4874
4875 if (r != PLUGIN_RET_OK)
4876 return r; // stop here
4877 }
4878
4879 return PLUGIN_RET_OK;
4880 }
4881
4882 static void plugins_done()
4883 {
4884 void *p;
4885
4886 ll_reset(loaded_plugins);
4887 while ((p = ll_next(loaded_plugins)))
4888 run_plugin_done(p);
4889 }
4890
4891 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struct in_addr *local)
4892 {
4893 struct nsctl request;
4894 struct nsctl response;
4895 int type = unpack_control(&request, buf, len);
4896 int r;
4897 void *p;
4898
4899 if (log_stream && config->debug >= 4)
4900 {
4901 if (type < 0)
4902 {
4903 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
4904 fmtaddr(addr->sin_addr.s_addr, 0), type);
4905 }
4906 else
4907 {
4908 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4909 dump_control(&request, log_stream);
4910 }
4911 }
4912
4913 switch (type)
4914 {
4915 case NSCTL_REQ_LOAD:
4916 if (request.argc != 1)
4917 {
4918 response.type = NSCTL_RES_ERR;
4919 response.argc = 1;
4920 response.argv[0] = "name of plugin required";
4921 }
4922 else if ((r = add_plugin(request.argv[0])) < 1)
4923 {
4924 response.type = NSCTL_RES_ERR;
4925 response.argc = 1;
4926 response.argv[0] = !r
4927 ? "plugin already loaded"
4928 : "error loading plugin";
4929 }
4930 else
4931 {
4932 response.type = NSCTL_RES_OK;
4933 response.argc = 0;
4934 }
4935
4936 break;
4937
4938 case NSCTL_REQ_UNLOAD:
4939 if (request.argc != 1)
4940 {
4941 response.type = NSCTL_RES_ERR;
4942 response.argc = 1;
4943 response.argv[0] = "name of plugin required";
4944 }
4945 else if ((r = remove_plugin(request.argv[0])) < 1)
4946 {
4947 response.type = NSCTL_RES_ERR;
4948 response.argc = 1;
4949 response.argv[0] = !r
4950 ? "plugin not loaded"
4951 : "plugin not found";
4952 }
4953 else
4954 {
4955 response.type = NSCTL_RES_OK;
4956 response.argc = 0;
4957 }
4958
4959 break;
4960
4961 case NSCTL_REQ_HELP:
4962 response.type = NSCTL_RES_OK;
4963 response.argc = 0;
4964
4965 ll_reset(loaded_plugins);
4966 while ((p = ll_next(loaded_plugins)))
4967 {
4968 char **help = dlsym(p, "plugin_control_help");
4969 while (response.argc < 0xff && help && *help)
4970 response.argv[response.argc++] = *help++;
4971 }
4972
4973 break;
4974
4975 case NSCTL_REQ_CONTROL:
4976 {
4977 struct param_control param = {
4978 config->cluster_iam_master,
4979 request.argc,
4980 request.argv,
4981 0,
4982 NULL,
4983 };
4984
4985 int r = run_plugins(PLUGIN_CONTROL, &param);
4986
4987 if (r == PLUGIN_RET_ERROR)
4988 {
4989 response.type = NSCTL_RES_ERR;
4990 response.argc = 1;
4991 response.argv[0] = param.additional
4992 ? param.additional
4993 : "error returned by plugin";
4994 }
4995 else if (r == PLUGIN_RET_NOTMASTER)
4996 {
4997 static char msg[] = "must be run on master: 000.000.000.000";
4998
4999 response.type = NSCTL_RES_ERR;
5000 response.argc = 1;
5001 if (config->cluster_master_address)
5002 {
5003 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
5004 response.argv[0] = msg;
5005 }
5006 else
5007 {
5008 response.argv[0] = "must be run on master: none elected";
5009 }
5010 }
5011 else if (!(param.response & NSCTL_RESPONSE))
5012 {
5013 response.type = NSCTL_RES_ERR;
5014 response.argc = 1;
5015 response.argv[0] = param.response
5016 ? "unrecognised response value from plugin"
5017 : "unhandled action";
5018 }
5019 else
5020 {
5021 response.type = param.response;
5022 response.argc = 0;
5023 if (param.additional)
5024 {
5025 response.argc = 1;
5026 response.argv[0] = param.additional;
5027 }
5028 }
5029 }
5030
5031 break;
5032
5033 default:
5034 response.type = NSCTL_RES_ERR;
5035 response.argc = 1;
5036 response.argv[0] = "error unpacking control packet";
5037 }
5038
5039 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
5040 if (!buf)
5041 {
5042 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
5043 return;
5044 }
5045
5046 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
5047 if (r > 0)
5048 {
5049 sendtofrom(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen, local);
5050 if (log_stream && config->debug >= 4)
5051 {
5052 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
5053 dump_control(&response, log_stream);
5054 }
5055 }
5056 else
5057 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
5058 fmtaddr(addr->sin_addr.s_addr, 0), r);
5059
5060 free(buf);
5061 }
5062
5063 static tunnelidt new_tunnel()
5064 {
5065 tunnelidt i;
5066 for (i = 1; i < MAXTUNNEL; i++)
5067 {
5068 if (tunnel[i].state == TUNNELFREE)
5069 {
5070 LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
5071 if (i > config->cluster_highest_tunnelid)
5072 config->cluster_highest_tunnelid = i;
5073 return i;
5074 }
5075 }
5076 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
5077 return 0;
5078 }
5079
5080 //
5081 // We're becoming the master. Do any required setup..
5082 //
5083 // This is principally telling all the plugins that we're
5084 // now a master, and telling them about all the sessions
5085 // that are active too..
5086 //
5087 void become_master(void)
5088 {
5089 int s, i;
5090 static struct event_data d[RADIUS_FDS];
5091 struct epoll_event e;
5092
5093 run_plugins(PLUGIN_BECOME_MASTER, NULL);
5094
5095 // running a bunch of iptables commands is slow and can cause
5096 // the master to drop tunnels on takeover--kludge around the
5097 // problem by forking for the moment (note: race)
5098 if (!fork_and_close())
5099 {
5100 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5101 {
5102 if (!session[s].opened) // Not an in-use session.
5103 continue;
5104
5105 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
5106 }
5107 exit(0);
5108 }
5109
5110 // add radius fds
5111 e.events = EPOLLIN;
5112 for (i = 0; i < RADIUS_FDS; i++)
5113 {
5114 d[i].type = FD_TYPE_RADIUS;
5115 d[i].index = i;
5116 e.data.ptr = &d[i];
5117
5118 epoll_ctl(epollfd, EPOLL_CTL_ADD, radfds[i], &e);
5119 }
5120 }
5121
5122 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
5123 {
5124 int s, i;
5125 int count = 0;
5126 int buckets[64];
5127
5128 if (CLI_HELP_REQUESTED)
5129 return CLI_HELP_NO_ARGS;
5130
5131 time(&time_now);
5132 for (i = 0; i < 64;++i) buckets[i] = 0;
5133
5134 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5135 {
5136 int idle;
5137 if (!session[s].opened)
5138 continue;
5139
5140 idle = time_now - session[s].last_packet;
5141 idle /= 5 ; // In multiples of 5 seconds.
5142 if (idle < 0)
5143 idle = 0;
5144 if (idle > 63)
5145 idle = 63;
5146
5147 ++count;
5148 ++buckets[idle];
5149 }
5150
5151 for (i = 0; i < 63; ++i)
5152 {
5153 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
5154 }
5155 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
5156 cli_print(cli, "%d total sessions open.", count);
5157 return CLI_OK;
5158 }
5159
5160 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
5161 {
5162 int s, i;
5163 int count = 0;
5164 int buckets[64];
5165
5166 if (CLI_HELP_REQUESTED)
5167 return CLI_HELP_NO_ARGS;
5168
5169 time(&time_now);
5170 for (i = 0; i < 64;++i) buckets[i] = 0;
5171
5172 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5173 {
5174 int open = 0, d;
5175 if (!session[s].opened)
5176 continue;
5177
5178 d = time_now - session[s].opened;
5179 if (d < 0)
5180 d = 0;
5181 while (d > 1 && open < 32)
5182 {
5183 ++open;
5184 d >>= 1; // half.
5185 }
5186 ++count;
5187 ++buckets[open];
5188 }
5189
5190 s = 1;
5191 for (i = 0; i < 30; ++i)
5192 {
5193 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
5194 s <<= 1;
5195 }
5196 cli_print(cli, "%d total sessions open.", count);
5197 return CLI_OK;
5198 }
5199
5200 /* Unhide an avp.
5201 *
5202 * This unencodes the AVP using the L2TP secret and the previously
5203 * stored random vector. It overwrites the hidden data with the
5204 * unhidden AVP subformat.
5205 */
5206 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
5207 {
5208 MD5_CTX ctx;
5209 uint8_t digest[16];
5210 uint8_t *last;
5211 size_t d = 0;
5212 uint16_t m = htons(type);
5213
5214 // Compute initial pad
5215 MD5_Init(&ctx);
5216 MD5_Update(&ctx, (unsigned char *) &m, 2);
5217 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
5218 MD5_Update(&ctx, vector, vec_len);
5219 MD5_Final(digest, &ctx);
5220
5221 // pointer to last decoded 16 octets
5222 last = value;
5223
5224 while (len > 0)
5225 {
5226 // calculate a new pad based on the last decoded block
5227 if (d >= sizeof(digest))
5228 {
5229 MD5_Init(&ctx);
5230 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
5231 MD5_Update(&ctx, last, sizeof(digest));
5232 MD5_Final(digest, &ctx);
5233
5234 d = 0;
5235 last = value;
5236 }
5237
5238 *value++ ^= digest[d++];
5239 len--;
5240 }
5241 }
5242
5243 int find_filter(char const *name, size_t len)
5244 {
5245 int free = -1;
5246 int i;
5247
5248 for (i = 0; i < MAXFILTER; i++)
5249 {
5250 if (!*ip_filters[i].name)
5251 {
5252 if (free < 0)
5253 free = i;
5254
5255 continue;
5256 }
5257
5258 if (strlen(ip_filters[i].name) != len)
5259 continue;
5260
5261 if (!strncmp(ip_filters[i].name, name, len))
5262 return i;
5263 }
5264
5265 return free;
5266 }
5267
5268 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
5269 {
5270 switch (p->op)
5271 {
5272 case FILTER_PORT_OP_EQ: return port == p->port;
5273 case FILTER_PORT_OP_NEQ: return port != p->port;
5274 case FILTER_PORT_OP_GT: return port > p->port;
5275 case FILTER_PORT_OP_LT: return port < p->port;
5276 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
5277 }
5278
5279 return 0;
5280 }
5281
5282 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
5283 {
5284 switch (op)
5285 {
5286 case FILTER_FLAG_OP_ANY:
5287 return (flags & sflags) || (~flags & cflags);
5288
5289 case FILTER_FLAG_OP_ALL:
5290 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
5291
5292 case FILTER_FLAG_OP_EST:
5293 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
5294 }
5295
5296 return 0;
5297 }
5298
5299 int ip_filter(uint8_t *buf, int len, uint8_t filter)
5300 {
5301 uint16_t frag_offset;
5302 uint8_t proto;
5303 in_addr_t src_ip;
5304 in_addr_t dst_ip;
5305 uint16_t src_port = 0;
5306 uint16_t dst_port = 0;
5307 uint8_t flags = 0;
5308 ip_filter_rulet *rule;
5309
5310 if (len < 20) // up to end of destination address
5311 return 0;
5312
5313 if ((*buf >> 4) != 4) // IPv4
5314 return 0;
5315
5316 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
5317 proto = buf[9];
5318 src_ip = *(in_addr_t *) (buf + 12);
5319 dst_ip = *(in_addr_t *) (buf + 16);
5320
5321 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
5322 {
5323 int l = (buf[0] & 0xf) * 4; // length of IP header
5324 if (len < l + 4) // ports
5325 return 0;
5326
5327 src_port = ntohs(*(uint16_t *) (buf + l));
5328 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
5329 if (proto == IPPROTO_TCP)
5330 {
5331 if (len < l + 14) // flags
5332 return 0;
5333
5334 flags = buf[l + 13] & 0x3f;
5335 }
5336 }
5337
5338 for (rule = ip_filters[filter].rules; rule->action; rule++)
5339 {
5340 if (rule->proto != IPPROTO_IP && proto != rule->proto)
5341 continue;
5342
5343 if (rule->src_wild != INADDR_BROADCAST &&
5344 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
5345 continue;
5346
5347 if (rule->dst_wild != INADDR_BROADCAST &&
5348 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
5349 continue;
5350
5351 if (frag_offset)
5352 {
5353 // layer 4 deny rules are skipped
5354 if (rule->action == FILTER_ACTION_DENY &&
5355 (rule->src_ports.op || rule->dst_ports.op || rule->tcp_flag_op))
5356 continue;
5357 }
5358 else
5359 {
5360 if (rule->frag)
5361 continue;
5362
5363 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
5364 {
5365 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
5366 continue;
5367
5368 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
5369 continue;
5370
5371 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
5372 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
5373 continue;
5374 }
5375 }
5376
5377 // matched
5378 rule->counter++;
5379 return rule->action == FILTER_ACTION_PERMIT;
5380 }
5381
5382 // default deny
5383 return 0;
5384 }